Le-yi Tu,Guo-min Yng,Xing-yng Zhng,b,Shui-ming Hu?.Hefei Ntionl Lbortory for Physicl Sciences t the Microscle,University of Science nd Technology of Chin,Hefei 230026,Chinb.Institute of Hydrogeology nd Environmentl Geology,Chinese Acdemy of Geologicl Sciences, Zhengding 050803,Chin(Dted:Received on October 9,2015;Accepted on December 24,2015)

?

ARTICLE E ffi cient Separation of Ar and Kr from Environmental Samples for Trace Radioactive Noble Gas Detection?

Le-yi Tua,Guo-min Yanga,Xiang-yang Zhanga,b,Shui-ming Hua?
a.Hefei National Laboratory for Physical Sciences at the Microscale,University of Science and Technology of China,Hefei 230026,China
b.Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geological Sciences, Zhengding 050803,China
(Dated:Received on October 9,2015;Accepted on December 24,2015)

Radioactive noble-gas isotopes,85Kr(half-life t1/2=10.8 y),39Ar(t1/2=269 y),and81Kr (t1/2=229,000 y),are ideal tracers and can be detected by atom trap trace analysis(ATTA), a laser-based technique,from environmental samples like air and groundwater.Prior to ATTA measurements,it is necessary to e ffi ciently extract krypton and argon gases from samples.Using a combination of cryogenic distillation,titanium chemical reaction and gas chromatography,we demonstrate that we can recover both krypton and argon gases from 1?10 L“air-like”samples with yields in excess of 90%and 98%,respectively,which meet well the requirements for ATTA measurements.A group of testing samples are analyzed to verify the performance of the system,including two groundwater samples obtained from north China plain.

Key words:Atom trap trace analysis,Gas chromatography,Radioactive noble gas

?Part of the special issue for“the Chinese Chemical Society’s 14th National Chemical Dynamics Symposium”.

?Author to whom correspondence should be addressed.E-mail: smhu@ustc.edu.cn

I.INTRODUCTION

Owing to the unique properties of noble gases,three radioactive isotopes,85Kr(half-life t1/2=10.8 y),39Ar (t1/2=269 y)and81Kr(t1/2=229 ky),are homogeneously distributed in the atmosphere,and have simple mixing and transportation mechanisms in the environment.They are considered as ideal tracers in various studies,including groundwater dating,ocean ventilation,and nuclear safety.85Kr is a fi ssion product emitted to the northern hemisphere since the nuclear age[1].85Kr can be used to monitor anthropic nuclear activities and to calibrate atmospheric transport models[2,3].It can also be used as a tracer for dating young groundwater with an age range of 2?50 y[4?8].81Kr is a cosmogenic nuclide,and human nuclear activities have no detectable e ff ect on the abundance of81Kr.These outstanding characteristics make81Kr a desired tracer for dating old groundwater[9?12]and ices[13]on the time scale of 50?1000 ky.39Ar in the atmosphere is also produced by cosmic-ray,which is particularly interested for studies of deep ocean mixing and circulation on a time scale of 50?1000 y, fi lling a time window inaccessible by other radioactive tracers[14?17].

The concentration of krypton in the earth’s atmosphere is 1.14 ppm(part per million)by volume[18]. The isotopic abundances of85Kr and81Kr have been determined to be 2.2×10?11and(5.2±0.6)×10?13,respectively[2,19?21].Argon constitutes 0.934%of the atmosphere by volume,larger than krypton by four orders of magnitude,but the isotopic abundance of39Ar is only 8×10?16.85Kr and39Ar can be analyzed by lowlevel counting(LLC)of the decay.The minimal sample size of LLC analysis of85Kr is about 10μL krypton (STP,standard temperature and pressure),and several hundred milliliters argon(STP)for39Ar.The later one corresponds to a groundwater sample size of several tons[21].Due to much longer half-life time of81Kr, it is impractical to analyze81Kr with LLC.Accelerator mass spectrometry(AMS)has been successfully applied for81Kr-dating,but the sample size was huge:about 500μL krypton gas recovered from 16 ton groundwater [10].Atom trap trace analysis(ATTA)[22]is a laserbased technique,utilizing a magneto-optical trap to selectively capture and count atoms.The minimum krypton sample size for85Kr/81Kr detection with ATTA has been reduced to a few microliter[23?25].ATTA analysis of39Ar also becomes feasible[26,27].It has been concluded[28]that ATTA is currently the most practical method of dating environmental samples using radioactive krypton and argon isotopes.

One liter of modern groundwater at 10?C contains about 5800085Kr atoms,130081Kr atoms,and 850039Ar atoms[29,30].Currently,ATTA measurement of radio-krypton needs a typical groundwater sample size of about 100 L.Prior to the ATTA measurement,it is necessary to extract noble gases(mostly argon andkrypton)from groundwater samples,and it can be accomplished in two steps: fi rst to extract the solved gas from groundwater,and then to separate krypton/argon from the“air-like”gas sample.Taking into account the complicated transfer and mixing of groundwater,analysis with multiple tracers is preferred in groundwater dating.Therefore,it is desired to separate and recover both argon and krypton from di ff erent gas samples with high yields to prevent any possible isotopic fractionation.

There have been several reports on the systems of Kr separation from“air-like”gases[5,10,25,31?33]. A method based on frozen charcoal trap and gas chromatography[5,32]has been applied for several liters of gas samples extracted from groundwater.A special krypton puri fi cation system for more than 100 L of bulk gas was reported by using several gas chromatographic steps,which has been applied in81Kr dating with AMS [10].Systems for recovering krypton from gases with a volume in the range of 1?100 liters have also been built based on cryogenic distillation,gas chromatography,and titanium reactions[25,33],and they have been successfully applied in radio-krypton dating measurements using ATTA.Here we report on a new system developed to recover both krypton and argon for ATTA measurements using 1?10 L gas extracted from groundwater samples.Using a combined process of cryogenic distillation,gas chromatography and titanium reaction, yields in excess of 90%and 99%have been achieved for krypton and argon,respectively.As a demonstration, abundances of85Kr and81Kr in several environmental samples have been determined by the ATTA instrument in Hefei(China).

II.EXPERIMENTS

A.Sampling in the fi eld:extract gases from groundwater

The con fi guration of the sampling system for fi eld sampling is shown in Fig.1.A membrane contactor (Liquicel,4×13,type X40)is used to extract gases from groundwater.The hydrophobic hollow- fi bre membrane contactor can e ffi ciently separate gases from liquid[34],and has been widely used in di ff erent applications[35?38].High e ffi ciency and simple structure make it very suitable to be used in fi eld.Groundwater sample fi rst passes through two fi ne fi lters to remove particles in the sample,then is introduced into the membrane contactor with a fl ow rate of 5?20 L/min monitored by a water fl ow meter.The contactor allows gases to di ff use from the water into gas- fi lled contactor pores which contact with gas line directly.The gas line is fi rst evacuated by a diaphragm pump and is further purged by the gas extracted from groundwater.When the size of the residual air is believed to be negligible, the extracted gas will be pumped into a sample cylinder by the diaphragm pump.Under a water fl ow rate of 10 L/min,about 5 L aqueous gas can be collected in about 0.5 h,with an extraction e ffi ciency of about 90% for Ar and O2and 70%for Kr.The exhaust end of the diaphragm pump connects with a sample cylinder,and the pressure of the fi nal collected gas is limited to be about 1.2 bar.More gas can be collected in the same cylinder if a compressor pump is used,but it considerably increases the weight of the system and consumes more power in the fi eld.

FIG.1 Schematic of the system for groundwater degassing. Abbreviations:W1 and W2:water valve,V1 and V2:threeway valve,P:pressure gauge.

Gas samples extracted from groundwater are contained in cylinders in the fi eld.Noble gases in the samples,mainly argon and krypton,will be extracted in the laboratories using cryogenic distillation and hightemperature Ti-reaction,followed by gas chromatographic separation.A schematic of the puri fi cation system is shown in Fig.2.

B.Cryogenic distillation and high-temperature Ti-reaction

Water vapor and carbon dioxide are fi rst removed by a molecular sieve 5?A trap(MS 5A),then the gas sample is introduced into a liquid-N2(77 K)cooled charcoal trap(trap 1,200 cm3volume,4 g charcoal of 16?32 mesh).A vacuum compressor is used and typically it takes about 30 min to condense more than 95% of the gas sample into trap 1.The vapor above the condensed sample in trap 1 fl ows into a quartz tube with a fl ow rate of about 50 mL/min,which is constrained by a mass fl ow controller.The quartz tube(“burner”) is 34 mm in diameter,70 cm long,and O-ring sealed at both ends.The tube has been fi lled with about 200 g titanium sponge,and slowly heated to 1000?C by a furnace.At temperature of 1000?C,titanium reacts with gaseous O2and N2to form titanium oxides and titanium nitrides,respectively.Titanium also consumes other chemically active gases,including CH4at such high temperature.Consequently,residual gases in the burner are mostly noble gases,together with little amounts of N2and CH4.The fl ow rate of 50 mL/min isselected to keep a mild reaction rate to avoid overheating the burner.During the process,the pressure in the quartz tube is monitored with a gauge(MKS Baratron 627B,relative accuracy of 0.12%).Because krypton has a lower vapor pressure in liquid-N2cooled charcoal trap, krypton is kept condensed in trap 1,while most Ar,O2, and N2gases are released to the burner.

FIG.2 Schematic of the system to separate krypton and argon from air-like samples.MS 5A:molecular sieve 5?A trap. Trap:frozen trap with activated charcoal.Furnace:furnace for titanium-reaction.Getter:titanium getter pump.GC:gas chromatography.

When the argon gas accumulates in the burner,the gas pressure gets higher and prevents the gas fl ow from trap 1 to the burner.At this point,we turn o ff the gas fl ow into the burner.The gas pressure in the burner will decrease since the Ti-reaction continues.It takes about 20 minutes to reach an equilibrium,which is illustrated in Fig.3(a).The residual gas(mostly argon)will be collected with another liquid-N2cooled charcoal trap (trap 2).Subsequently,we can turn on the gas fl ow from trap 1 to the burner again and restart the distillation. The procedure above can be repeated until most gas in Trap 1 is transferred,which is evidenced by a sudden drop of fl ow rate from trap 1 to the burner.Usually two iterations are needed for a sample with an original size of 10 L.We have investigated the composition of the gas fl ow during the process using gas chromatographic analysis,which is shown in Fig.3(b).At the beginning, the main composition is N2.Later when N2depletes, O2and Ar become dominant in the fl ow.Finally,the fl ow stops when O2and Ar deplete.

When all the gas in the burner is collected in trap 2,the residual gas in trap 1 will be released by heating the trap to about 200?C.It contains all the krypton in the original sample,but being still mostly N2and O2, together with methane and some argon.The typical size is about 0.3 L(excluding methane).The gas released from trap 1 is also introduced to the burner with a fl ow rate controlled to be less than 50 mL/min.

When most N2,O2and CH4are removed in the burner,the residual gas is transferred to another activated liquid-N2cooled charcoal trap(trap 3,10 mL volume,1 g charcoal of 16?32 mesh).Typical time needed for the whole distillation and titanium reaction process is about 4 h for an air sample of 10 L.

FIG.3(a)Observed residual gas pressure in the“burner”during cryogenic distillation of an air sample of 10 L.(b)The measured fl ow rates of di ff erent gases.The total fl ow rate was controlled to be 50 mL/min by a mass fl ow controller. The distillation process was separated into two stages as indicated with vertical dotted lines.When the gas pressure in the“burner”is high,the gas fl ow is stopped for 20 min also and restarted when the argon gas is transferred to a cold trap.

C.Chromatographic separation of krypton

A gas chromatographic(GC)separation process is applied to extract krypton gas from the sample.The residual gas in trap 3 is released by heating the trap to 200?C and fl ushed into a chromatographic column.The column is fi lled with a molecular sieve(MS 5A,grain size of No.60?80,diameter of 6 mm,length of 2 m) and installed in a constant temperature bath at 30?C. Pure helium(99.999%purity,30 mL/min)is used as carrier gas.Characteristic elution peaks of various gas components are monitored with a thermal conductivity detector(TCD),and they are shown in Fig.4.Because several milliliters of argon and almost all krypton(micro-liters)are presented here,the chromatographic separation process includes a 2.5 min collection of argon and a 3 min collection of krypton,which is shown in Fig.4.

FIG.4 Chromatograms of the elution times of various gases originally extracted from an air-like sample.Two pairs of vertical dotted lines indicate the time ranges for Ar and Kr gas collection during 1st GC separation.The solid line shows the fi nal constituents of the Kr sample.

The collected argon gas,together with the gas previously stored in trap 2,is transferred into a chamber installed with a Ti-getter pump(Getter 1,500?C,Nanjing Huadong Electronics Co.)to get rid of residual N2. After that,the argon gas is collected in a sample holder fi lled with activated charcoal at liquid-N2temperature, and then stored at room temperature.A second run of chromatographic separation is applied to extract the Kr gas,which is also shown in Fig.4.Then a getter process is applied to remove residual contaminants from the obtained krypton sample.Finally,the puri fi ed krypton gas is also collected in a sample holder fi lled with activated charcoal at liquid-N2temperature,being ready for ATTA measurement.The duration of the GC separation is about 1 h.

Note that the TCD signal in the GC process has been calibrated by using pure Ar,N2,Kr,and CH4samples. The areas under the chromatographic peaks are used to determine the contents of various components in the obtained krypton gas.The quantity of extracted argon is derived from the pressure gauge and the volume of the sample holder.Typically 90 mL argon can be obtained from an ambient air sample of 10 L(STP).

III.RESULTS AND DISCUSSION

A.Yield and purity of products

The e ffi ciency and purity of the extraction process were tested by several samples:ambient air samples with volumes varying from 1 L to 10 L(STP),two air samples of 10 L and mixed with 1%CH4,and two groundwater samples.The GC data of recovered krypton and argon gases are shown in Fig.5.The sizes of original samples and recovered Kr/Ar gases are presented in Table I.

FIG.5 Chromatograms of the fi nal components of(a)Kr and(b)Ar gases recovered from air samples of di ff erent sizes. The curve at the bottom of each panel is from a blank sample (pure helium).

Although Ar and N2contents are observed from the chromatography spectra(Fig.5(a)),which may result from air leak during the collection process.The size of “impurities”in obtained Kr samples becomes relatively larger when the original sample size gets smaller.Since only 1 ppm of ambient air is krypton,even at the worst case(1 L air sample,Fig.5(a)),the content of contaminated krypton relative to the whole krypton sample size is less than 0.1%and therefore negligible.

A small N2peak also presents in the TCD spectra of the recovered argon sample(Fig.5(b)).It indicates that the Ti-reaction and getter cannot completely remove N2from the argon sample.But the content of N2is below 1%.In addition,we cannot detect any loss of krypton(＜0.1%)in the distillation process.Since the residual small impurities have no in fl uence on ATTA measurements,there is no need of further e ff orts to remove the impurities from the obtained krypton and argon samples.

For ambient air gases and CH4-rich samples,the yields of Kr and Ar are more than 85%and 90%,respectively.The O2-poor samples were extracted in fi eld from groundwater,and their initial constituents were analyzed by gas chromatography.Although original krypton contents in these two samples are too small

TABLE I The quality of processed gas(content of Kr inμL,content of Ar in mL),extraction yield(in%)and purity(in %)of Kr and Ara.

aThere is an uncertainty of 2.5%in the given yields of krypton and argon.

bCalculated values from krypton concentration of 1.14 ppm by volume in the earth’s atmosphere.cCalculated values from argon concentration of 0.934%.

dGas mixture with enriched CH4.

eDissolved gas samples extracted from groundwater. to be determined by conventional chromatography,the sizes of recovered krypton gases agree reasonably with the estimated values according to the solubility of krypton and the temperature of the groundwater.

B.Isotopic fractionation and environmental samples

The extracted krypton gas is ready for ATTA measurements.Figure 6 shows the fl uorescence signal of the trapped stable krypton isotopes when scanning the laser frequency.Two krypton samples were tested,one is a commercial pure krypton gas sample bought in 2007 (denoted as“2007 bottle”),and the other one is from a groundwater sample(the last sample shown in Table I). As shown in the fi gure,relative intensities of respective isotopes remain the same in both samples,indicating no detectable isotopic fractionation e ff ect in the gas extraction and puri fi cation process.When the laser frequency is set on resonance with the rare isotope85Kr or81Kr, image of single atoms will be detected by a sensitive EMCCD camera and counts of individual atoms will be used to derive the isotopic abundances[24].Two “O2-poor”samples extracted from deep groundwater obtained in north China plain are presented in Table I as application examples of the system.For the fi rst sample,5 counts of85Kr and 228 counts of81Kr have been obtained in 4 h.The isotopic abundances of85Kr and81Kr,relative to the modern values,are determined to be 0.3%and 71±5%,respectively,which leads to a81Kr age of about 113±23 ky.For the second sample, 18 counts of85Kr and 411 counts of81Kr have been recorded in 4 h.The relative-to-modern isotopic abundances of85Kr and81Kr are 0.6%and 106±6%,respectively.It indicates that the age of this groundwater sample is beyond both detection ranges of85Kr and81Kr,and should be older than 50 y.The very low85Kr counts also indicate that air contamination throughout the sample extraction and puri fi cation process is negligible.

FIG.6 The fl uorescence spectra of krypton recovered from one groundwater sample and the“standard”krypton from a commercial gas bottle in 2007.The spectra show stable isotopes of krypton(78Kr,80Kr,82Kr,83Kr,84Kr and86Kr) and their relative abundances,and demonstrates that there is no signi fi cant isotopic fractionation throughout the whole krypton separation process.Two arrows mark the position of the two rare isotopes81Kr and85Kr.

IV.CONCLUSION

we have developed an apparatus to extract krypton and argon gases from air-like gas samples using a combination of cryogenic distillation,chemical absorption by titanium,and gas chromatography.A portable sampling instrument has also been developed to extract solved air from groundwater samples in the fi eld.The system has been tested by applying several di ff erent gas samples,including ambient air samples with a size of 1?10 L,synthesized CH4enriched samples which mimic gases extracted from groundwater,and also two samplesobtained from real groundwater in the fi eld.Krypton and argon gases can be separated with an e ffi ciency better than 90%.The system ful fi lls present needs of the ATTA measurement of the rare noble-gas isotopes including85Kr,81Kr and39Ar.

V.ACKNOWLEDGMENTS

This work was supported by the Special Fund for Land and Resources Research in the Public Interest (No.201511046)and the National Natural Science Foundation of China(No.21225314 and No.41102151).We would like to give our gratitude to Zong-yu Chen from IHEG for organizing the fi eld campaign.

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Chinese Abstracts(中文摘要)

時(shí)間分辨偏振紅外光譜及其應(yīng)用.................................1張文凱?(北京師范大學(xué)高等量子研究中心，物理系，北京100875)

摘要：時(shí)間分辨偏振紅外光譜已被廣泛應(yīng)用于研究光化學(xué)過(guò)程中的分子結(jié)構(gòu)動(dòng)力學(xué).通過(guò)測(cè)定瞬態(tài)物質(zhì)躍遷偶極矩之間的角度等結(jié)構(gòu)信息，可以提供光化學(xué)過(guò)程中伴隨的電荷分布、分子結(jié)構(gòu)和構(gòu)象變化等動(dòng)態(tài)信息.包括簡(jiǎn)要介紹時(shí)間分辨偏振紅外光譜技術(shù)的原理和應(yīng)用：(i)時(shí)間分辨偏振紅外光譜概述；(ii)時(shí)間分辨偏振紅外光譜的原理及其優(yōu)勢(shì)；(iii)利用時(shí)間分辨偏振紅外光譜探測(cè)多種化學(xué)動(dòng)力學(xué)過(guò)程，例如蛋白質(zhì)構(gòu)象動(dòng)力學(xué)、激發(fā)態(tài)的電子局域化和光致異構(gòu)化等；(iv)時(shí)間分辨偏振紅外光譜的局限和發(fā)展前景. 利用基質(zhì)隔離紅外光譜結(jié)合理論計(jì)算，研究了激光濺射獲得的第五族金屬原子和硫化氫分子的反應(yīng).結(jié)果表明金屬原子插入H2S的H?S化學(xué)鏈形成HMSH分子(M=V，Nb，Ta). 對(duì)Nb和Ta該HMSH分子重排為H2MS分子.HMSH分子和H2S進(jìn)一步反應(yīng)生成H2M(SH)2分子.通過(guò)S同位素標(biāo)定確定了產(chǎn)物的分子結(jié)構(gòu)，同時(shí)我們用DFT(B3LYP和BPW91)理論計(jì)算預(yù)測(cè)了產(chǎn)物分子的能量、結(jié)構(gòu)和振動(dòng)頻率.通過(guò)DFT IRC計(jì)算研究了第五族金屬原子和2S分子的反應(yīng)機(jī)理.HVSH分子通過(guò)光照解離為VS和H2，然后通過(guò)退火可以發(fā)生VS和H2復(fù)合反應(yīng).計(jì)算表明HVSH釋放H2需要16.9 kcal/mol的活化能及吸熱13.5 kcal/mol. 采用共振拉曼光譜學(xué)和完全活化空間自洽場(chǎng)方法研究了苯基疊氮被激發(fā)到S2(A＇)、S3(A＇)和S6(A＇)光吸收態(tài)后的結(jié)構(gòu)動(dòng)力學(xué).基于傅立葉變換拉曼、傅立葉變換紅外、紫外、密度泛函計(jì)算和簡(jiǎn)正模式分析，指認(rèn)了紫外吸收光譜和振動(dòng)光譜.獲得了環(huán)己烷、乙腈和甲醇溶劑中273.9、252.7、245.9、228.7、223.1和208.8 nm等不同激發(fā)波長(zhǎng)下的A、B和C帶共振拉曼光譜，以探測(cè)Franck-Condon區(qū)域的結(jié)構(gòu)動(dòng)力學(xué).CASSCF計(jì)算獲得了單重電子激發(fā)態(tài)能量最低點(diǎn)和勢(shì)能面交叉點(diǎn)的電子激發(fā)能和優(yōu)化幾何結(jié)構(gòu).結(jié)果表明，苯基疊氮在S2(A＇)、S3(A＇)和S6(A＇)態(tài)上的激發(fā)態(tài)結(jié)構(gòu)動(dòng)力學(xué)各不相同.與Kasha規(guī)則相符，S2S1(1)和S2S1(2)勢(shì)能面交叉點(diǎn)在S2(A＇)激發(fā)態(tài)衰變動(dòng)力學(xué)和N7=N8鏈解離中扮演著重要角色.提出了兩條主要衰減通道：S2,min→S0輻射通道和S2,FC(ππ?)→S2(ππ?)/S1(nπ?)→S1(nπ?)非輻射通道. 利用團(tuán)簇模型研究了質(zhì)子化水團(tuán)簇對(duì)乙炔的溶劑化作用. H+(C2H2)(H2O)n(n=1～5)的量子化學(xué)計(jì)算結(jié)果表明，水分子傾向與乙炔的π電子形成新型OH···π氫鏈作用，并且乙炔的第一溶劑層需要4個(gè)水分子來(lái)完成.模擬的紅外光譜揭示了OH···π氫鏈作用后的OH伸縮振動(dòng)是研究乙炔與水溶劑化過(guò)程的靈敏探針.這些紅外光譜可以用紅外光解離光譜實(shí)驗(yàn)方法測(cè)得，將為理解OH···π氫鏈作用以及質(zhì)子化水團(tuán)簇如何溶劑化乙炔提供有力的科學(xué)數(shù)據(jù). 利用高精度的CASSCF和MS-CASPT2電子結(jié)構(gòu)計(jì)算方法系統(tǒng)地研究了2-(2＇-羥基苯基)-4-甲基噁唑的光物理和光化學(xué)機(jī)理. 在CASSCF級(jí)別，首先優(yōu)化得到勢(shì)能面極小結(jié)構(gòu)和圓錐交叉結(jié)構(gòu)，及激發(fā)態(tài)質(zhì)子轉(zhuǎn)移、異構(gòu)化、和失活的極小能量路徑.然后用MS- 利用脈沖激光濺射-超聲分子束載帶方法制備氣相硼羰基絡(luò)合物正離子.采用紅外光解離光譜研究了、和B2(CO)4+的振動(dòng)光譜.研究結(jié)果表明具有非常強(qiáng)的B?CO鏈，無(wú)法直接獲得其紅外光解離光譜.對(duì)B(CO)4+的光解離光譜研究表明該離子是一個(gè)B(CO)3+和CO之間弱相互作用絡(luò)合物.其中B核具有平面D3h對(duì)稱性結(jié)構(gòu)，中心硼具有穩(wěn)定的8電子組態(tài).具有平面的D2h對(duì)稱性結(jié)構(gòu)，其中的B?B鏈包含一個(gè)σ鏈和半個(gè)π鏈.自然軌道能量分解分析(EDA-NOCV)表明在B(CO中的B?CO成鏈作用中OC→B(σ)要比B→CO(π)反饋?zhàn)饔脧?qiáng). 利用飛秒時(shí)間分辨質(zhì)譜技術(shù)研究了鄰碘甲苯分子在266 nm激發(fā)下的光解動(dòng)力學(xué).光解產(chǎn)物碎片通過(guò)800 nm強(qiáng)激光場(chǎng)下的多光子電離實(shí)現(xiàn)探測(cè).擬合光解產(chǎn)物C7H7自由基和I原子隨泵浦-探測(cè)延遲時(shí)間變化的信號(hào)，得到解離時(shí)間為380±50 fs，它反映的是266 nm同時(shí)激發(fā)nσ?和ππ?態(tài)后C?I鏈的平均解離時(shí)間.此外，還利用基態(tài)碘原子的共振波長(zhǎng)298.23 nm作為探測(cè)光，通過(guò)共振增強(qiáng)多光子電離方法對(duì)解離生成的基態(tài)碘原子進(jìn)行了選擇性探測(cè).擬合I+隨泵浦-探測(cè)延遲時(shí)間變化的信號(hào)，得到解離時(shí)間為400±50 fs，這與通過(guò)800 nm多光子電離得到的解離時(shí)間一致，表明解離生成的主要產(chǎn)物是基態(tài)碘原子. 通過(guò)采用真空紫外(VUV)激光速度-地圖成像-TPE(真空紫外VMI-TPE)方法獲得了高分辨率初始光電子(TPE)氯苯)的光譜，炔丙基自由基)和烯丙基.觀察到的真空紫外VMI-TPE方法的光電子能量分辨率在1～2 cm?1，可以和在真空紫外激光脈沖場(chǎng)電離光電子(VUV-PFI-PE)的測(cè)量媲美.類似真空紫外PFI-PE測(cè)量，真空紫外VMI-光電子(真空紫外VMI-PE)和真空紫外VMI-TPE測(cè)量能量分辨率依賴于直流電場(chǎng)在光電離區(qū)加速電子.C6H5Cl和C3H3的電離初始值的降低為F的函數(shù)表示Stark偏移校正為VUV-VMI-TPE測(cè)量由?3.1√ 報(bào)道和頻振動(dòng)光譜在交叉?zhèn)鞑サ膶?shí)驗(yàn)構(gòu)型下的理論公式推導(dǎo)和實(shí)驗(yàn)結(jié)果.在交叉?zhèn)鞑サ暮皖l振動(dòng)光譜實(shí)驗(yàn)室中，可見光和紅外光通過(guò)相互垂直的入射面同時(shí)照射在界面上，從而避免了對(duì)使用同時(shí)能夠透過(guò)可見和紅外激光束的光學(xué)元件的要求.這種交叉實(shí)驗(yàn)構(gòu)型能夠直接應(yīng)用到封閉在真空或者壓力腔體中的界面，使得在用遠(yuǎn)紅外直接探測(cè)金屬氧化物及其它低頻界面振動(dòng)模式實(shí)驗(yàn)的窗口材料有更多的選擇. 利用超快泵浦探測(cè)紅外光譜、穩(wěn)態(tài)線性紅外光譜和計(jì)算化學(xué)方法，對(duì)過(guò)渡金屬羰基化合物Mn(CO)5Br和Re(CO)5Br的振動(dòng)和結(jié)構(gòu)動(dòng)力學(xué)進(jìn)行了研究.借助羰基的兩個(gè)伸縮振動(dòng)峰(處于低頻的A1模式和處于高頻的簡(jiǎn)并E模式)進(jìn)行了觀測(cè).結(jié)果表明，在兩個(gè)配合物中，A1和E模式振動(dòng)峰的振動(dòng)頻率位置及頻率差都與中心金屬原子對(duì)羰基的鏈級(jí)和振動(dòng)力常數(shù)的影響相關(guān).而A1模式比E模式的線寬寬一些，部分由于振動(dòng)壽命的影響.此外，從瞬態(tài)光譜中獲得了振動(dòng)模式依賴的對(duì)角非諧性常數(shù)，發(fā)現(xiàn)在兩個(gè)羰基化合物中E模式的非諧性總是較小. 電化學(xué)反應(yīng)在許多學(xué)科中扮演著很重要的角色.對(duì)于化學(xué)分析來(lái)說(shuō)，振動(dòng)光譜是一門很好的原位測(cè)量技術(shù)，然而由于紅外光在電極和電解質(zhì)中強(qiáng)烈的衰減使得它在電化學(xué)反應(yīng)中的應(yīng)用受到了很大的限制.本文中論證了在金屬電極上結(jié)合適當(dāng)?shù)膩啿ㄩL(zhǎng)等離子體結(jié)構(gòu)，在OH伸縮振動(dòng)頻段內(nèi)，通過(guò)激發(fā)表面等離激元能夠大大增強(qiáng)金屬與液態(tài)水電化學(xué)界面的紅外場(chǎng)強(qiáng).這對(duì)于原位振動(dòng)光譜的研究，特別是當(dāng)用到表面靈敏的光學(xué)混頻技術(shù)時(shí)可產(chǎn)生很大的促進(jìn)作用. 采用時(shí)間分辨紅外吸收光譜方法，研究了鄰甲基苯甲酸安息香酯在266 nm激光作用下發(fā)生的光化學(xué)反應(yīng)，并考察了溶劑對(duì)反應(yīng)過(guò)程的影響.從瞬態(tài)紅外光譜上觀察到了鄰甲基苯甲酸和苯甲酰自由基及苯偶酰，提供了直接的光譜證據(jù)證明了脫保護(hù)反應(yīng)及C?C=O處均裂反應(yīng)的發(fā)生.通過(guò)對(duì)比溶劑中不同水含量下均裂反應(yīng)中間體及鄰甲基苯甲酸的產(chǎn)率，發(fā)現(xiàn)水含量在溶劑中的增加能促進(jìn)脫保護(hù)反應(yīng)的發(fā)生.關(guān)鏈詞：安息香，籠化合物，光致脫保護(hù)反應(yīng)，時(shí)間分辨紅外吸收光譜 利用新建激光濺射交叉分子束裝置，結(jié)合時(shí)間切片速度成像技術(shù)開展了金屬原子態(tài)-態(tài)反應(yīng)動(dòng)力學(xué)的相關(guān)研究.超聲金屬原子束是由激光濺射金屬棒產(chǎn)生，結(jié)合無(wú)氣體溢流通道的自由擴(kuò)散設(shè)計(jì)，得到了質(zhì)量很好的金屬原子超聲束.本文選擇Al+O2反應(yīng)體系來(lái)測(cè)試新建金屬交叉分子束實(shí)驗(yàn)裝置的性能.通過(guò)(1+1)共振多光子電離技術(shù)，以AlO(D2Σ+)為中間態(tài)來(lái)探測(cè)特定轉(zhuǎn)動(dòng)態(tài)的產(chǎn)物AlO自由基.相同波長(zhǎng)下可以同時(shí)得到反應(yīng)產(chǎn)物AlO(X2Σ+，ν=0，N和N+14)兩個(gè)轉(zhuǎn)動(dòng)態(tài)的速度成像，分別對(duì)應(yīng)著?ν=1的P(N)和R(N+14)躍遷. 在244.145 nm同時(shí)探測(cè)到P(15)和R(29)的躍遷，形成的兩個(gè)環(huán)在切片成像圖中可以完全區(qū)分開，這兩個(gè)躍遷分別對(duì)應(yīng)著反應(yīng)產(chǎn)物AlO(ν=0，N=15)和AlO(ν=0，N=29)兩個(gè)轉(zhuǎn)動(dòng)態(tài).對(duì)應(yīng)此兩個(gè)轉(zhuǎn)動(dòng)態(tài)的能級(jí)差為403 cm?1.這兩個(gè)反應(yīng)產(chǎn)物轉(zhuǎn)動(dòng)態(tài)的區(qū)分表明了該實(shí)驗(yàn)裝置與最近的一篇研究報(bào)道[J.Chem.Phys.140,214304 (2014)]相比較，具有較好的碰撞能量分辨率. 通過(guò)雙光子光電子的方法探測(cè)了TiO2(011)-(2×1) 和TiO2(110)-(1×1)表面的光催化氧化甲醇的性質(zhì).在吸附了甲醇的二氧化鈦(011)和(110)界面處探測(cè)到了一個(gè)費(fèi)米能級(jí)以上2.5 eV的電子激發(fā)態(tài)，該電子激發(fā)態(tài)可作為測(cè)試二氧化鈦界面還原性的探針使用.利用此探針在甲醇/TiO2(011)-(2×1)和甲醇/TiO2(110)-(1×1)界面探測(cè)到了一個(gè)隨光照時(shí)間的電子激發(fā)態(tài)信號(hào)變化，這一變化可以歸于光催化生成的表面羥基對(duì)界面還原性的影響.由此得出的光催化氧化甲醇的速率TiO2(110)-(1×1)比TiO2(011)-(2×1)快了大約11.4倍.這可能由于表面原子結(jié)構(gòu)排布的原因不同.本工作不僅介紹了一個(gè)利用雙光子光電子能譜探測(cè)到的甲醇/TiO2界面電子結(jié)構(gòu)的細(xì)節(jié)特征，還揭示了表面結(jié)構(gòu)對(duì)二氧化鈦光反應(yīng)性質(zhì)的重要影響. 在量子動(dòng)力學(xué)計(jì)算中，有時(shí)候?yàn)榱艘?guī)避奇點(diǎn)問(wèn)題或者節(jié)省計(jì)算量，我們經(jīng)常需要對(duì)哈密頓量進(jìn)行變換.然而，在使用傅里葉基矢計(jì)算時(shí)，哈密頓量的變換形式容易導(dǎo)致哈密頓矩陣失去厄米性，進(jìn)而有些情況下使數(shù)值計(jì)算變得不穩(wěn)定.本文主要討論構(gòu)建具有厄米性的哈密頓算符的方法.以三原子分子為例，構(gòu)建了鏈長(zhǎng)—鏈角和Radau坐標(biāo)下描述分子運(yùn)動(dòng)的各種形式的哈密頓量.基于這些哈密頓量，采用含時(shí)波包方法計(jì)算了OClO分子的吸收光譜，討論了非厄米性矩陣對(duì)計(jì)算結(jié)果的影響.本文所得到的結(jié)論對(duì)基于基函數(shù)展開的量子動(dòng)力學(xué)計(jì)算都是適用的. 利用光電子能譜及密度泛函理論計(jì)算對(duì)TiGen?(n=7～12)團(tuán)簇的幾何結(jié)構(gòu)及電子特性等進(jìn)行了系統(tǒng)研究.對(duì)于TiGen?負(fù)離子及中性TiGen，在n=8時(shí)出現(xiàn)了鈦原子半內(nèi)嵌的船型結(jié)構(gòu)；在n=9～11時(shí)，新增的鍺原子加蓋到這種船型結(jié)構(gòu)上，逐步形成鈦原子完全內(nèi)嵌的結(jié)構(gòu).TiGe12?團(tuán)簇具有一種鈦原子內(nèi)嵌的變形六棱柱結(jié)構(gòu).自然布居分析結(jié)果顯示，對(duì)于n=8～12的TiGen?/0團(tuán)簇，隨著內(nèi)嵌結(jié)構(gòu)的形成，有電子從鍺原子轉(zhuǎn)移到鈦原子，說(shuō)明其電荷轉(zhuǎn)移方式與結(jié)構(gòu)演變密切相關(guān). 蛋白質(zhì)的酰胺A譜帶對(duì)蛋白質(zhì)的酰胺氫鏈結(jié)構(gòu)很敏感.然而由于該譜帶和水的OH伸縮振動(dòng)譜帶嚴(yán)重重疊，導(dǎo)致在蛋白質(zhì)水溶液中原位測(cè)量酰胺A譜帶依舊很困難.我們提出了一種新的分析方法用于原位測(cè)量水溶液中的酰胺A譜帶.這個(gè)方法稱為拉曼除譜法.將蛋白質(zhì)水溶液光譜除以純水光譜即可獲得拉曼除譜.利用數(shù)值模擬從數(shù)學(xué)上肯定了使用拉曼除譜可以直接獲得酰胺A譜帶.我們還通過(guò)測(cè)量溶菌酶和α-糜蛋白酶的固體和水溶液的拉曼光譜，這些光譜也證實(shí)了可以通過(guò)拉曼除譜法直接獲取酰胺A譜帶.利用拉曼除譜還分析了溶菌酶的熱變性過(guò)程.這些研究表明拉曼除譜可以原位地表征水溶液中的蛋白質(zhì)酰胺A譜帶. 利用激光閃光光解技術(shù)研究了蒽醌-2-磺酸鈉(AQS)在吡啶離子液體N-丁基吡啶四氟硼酸鹽([BPy][BF4])與水(H2O)混合體系中的光化學(xué)反應(yīng)過(guò)程.實(shí)驗(yàn)結(jié)果表明，AQS的激發(fā)三重態(tài)(3AQS?)會(huì)與H2O快速反應(yīng)，不斷增加[BPy][BF4]在混合體系中的體積比(VIL)，瞬態(tài)吸收光譜發(fā)生了很大變化.510 nm附近的瞬態(tài)吸收帶變化最大，在0＜VIL＜0.1時(shí)，吸光度會(huì)隨著[BPy][BF4]的增加而增加；而在VIL＞0.1時(shí)，吸光度則隨著比例的增加而減小.然而380 nm附近吸收帶的吸光度卻一直在增加.通過(guò)擬合近似地得到了瞬態(tài)物種B和3AQS?的表觀動(dòng)力學(xué)參數(shù).另外還討論了3AQS?與陽(yáng)離子之間的奪氫反應(yīng)，通過(guò)對(duì)350～420 nm處光譜圖的分析，推斷出這一范圍的瞬態(tài)吸收光譜是3AQS?與AQSH·的疊加譜.在混合體系 利用熒光非共線光參量放大光譜技術(shù)測(cè)量了DCM染料乙醇溶液的溶劑化動(dòng)力學(xué)過(guò)程.實(shí)驗(yàn)結(jié)果表明，瞬態(tài)熒光光譜經(jīng)過(guò)光譜矯正后，可以產(chǎn)生準(zhǔn)確的溶劑化相關(guān)函數(shù)以及溶劑化過(guò)程中瞬態(tài)光譜峰值頻率移動(dòng).本文的工作表明熒光非共線光參量放大光譜技術(shù)有益同時(shí)關(guān)注熒光強(qiáng)度動(dòng)力學(xué)以及光譜譜型演化的研究領(lǐng)域. 放射性惰性氣體同位素85Kr(半衰期為10.8年)、39Ar(半衰期為269年)和81Kr(半衰期為22.9萬(wàn)年)是理想的環(huán)境示蹤劑，基于激光技術(shù)的原子阱痕量分析方法(Atom trap trace analysis,ATTA)可以實(shí)現(xiàn)對(duì)空氣、地下水等環(huán)境樣品中這幾種同位素的有效探測(cè).在進(jìn)行ATTA測(cè)量之前，需要將樣品中的氪氣和氬氣有效分離出來(lái).利用低溫蒸餾、海綿鈦化學(xué)吸附和氣相色譜分離等技術(shù)，可以從1～10 L氣體樣品中分別提取出90%以上的氪氣和98%以上的氬氣，從而滿足ATTA測(cè)量的樣品要求.通過(guò)對(duì)包括兩個(gè)野外地下水樣品等一系列樣品進(jìn)行分離實(shí)驗(yàn)，驗(yàn)證了氣體分離裝置的可靠性能.

關(guān)鏈詞：超快光譜，紅外光譜，偏振，時(shí)間分辨紅外光譜

基質(zhì)隔離紅外光譜結(jié)合理論計(jì)算研究第五族金屬原子和硫化氫反應(yīng). ..............................................................11趙杰，許兵，俞文杰，王雪峰?(同濟(jì)大學(xué)化學(xué)系，上海市化學(xué)品分析、風(fēng)險(xiǎn)評(píng)估及控制重點(diǎn)實(shí)驗(yàn)室，上海200092)

關(guān)鏈詞：硫化氫，基質(zhì)隔離，過(guò)渡金屬，DFT理論計(jì)算

苯基疊氮在光吸收激發(fā)態(tài)上的結(jié)構(gòu)動(dòng)力學(xué)?共共振拉曼和量子力學(xué)計(jì)算研究.......................................................21袁榮單，薛佳舟，鄭旭明?(浙江理工大學(xué)化學(xué)系，杭州310018)

關(guān)鏈詞：苯基疊氮，結(jié)構(gòu)動(dòng)力學(xué)，衰減動(dòng)力學(xué)，共振拉曼光譜，CASSCF計(jì)算，錐形交叉點(diǎn)

質(zhì)子化水團(tuán)簇對(duì)乙炔溶劑化作用的結(jié)構(gòu)與紅外光譜.............31孔祥濤a，雷鑫a，袁勤勤a，張冰冰a,b，趙志a,c，楊冬a，蔣述康a，戴東旭a，江凌a?(a.中國(guó)科學(xué)院大連化學(xué)物理研究所，分子反應(yīng)動(dòng)力學(xué)國(guó)家重點(diǎn)實(shí)驗(yàn)室，能源材料化學(xué)協(xié)同創(chuàng)新中心，大連116023；b.大連理工大學(xué)，精細(xì)化工國(guó)家重點(diǎn)實(shí)驗(yàn)室，大連116024；c.大連理工大學(xué)，三束材料改性教育部重點(diǎn)實(shí)驗(yàn)室，大連116024)

關(guān)鏈詞：乙炔，水，溶劑化，紅外光解離光譜，量子化學(xué)計(jì)算

噁唑體系激發(fā)態(tài)質(zhì)子轉(zhuǎn)移和失活的理論研究...................38謝斌斌，李春香，崔剛龍?，方遒?(北京師范大學(xué)化學(xué)學(xué)院，理論與計(jì)算光化學(xué)教育部重點(diǎn)實(shí)驗(yàn)室，北京100875)

CASPT2方法對(duì)所有得到的結(jié)構(gòu)和能量路徑進(jìn)行單點(diǎn)能量校正，我們發(fā)現(xiàn)在含有OH···N氫鏈的構(gòu)象異構(gòu)體中，激發(fā)態(tài)質(zhì)子轉(zhuǎn)移基本上是一個(gè)無(wú)壘的過(guò)程；在含OH···O氫鏈的構(gòu)象異構(gòu)體中，激發(fā)態(tài)質(zhì)子轉(zhuǎn)移被抑制了.此外，找到兩個(gè)能量較低的酮式S1/S0圓錐交叉結(jié)構(gòu)，使得激發(fā)態(tài)質(zhì)子轉(zhuǎn)移生成的S1酮式結(jié)構(gòu)可以很快失活到達(dá)基態(tài).但是，醇式S1/S0圓錐交叉結(jié)構(gòu)能量較高，抑制了S1醇式結(jié)構(gòu)的激發(fā)態(tài)失活.

關(guān)鏈詞：激發(fā)態(tài)質(zhì)子轉(zhuǎn)移，光異構(gòu)化，圓錐交叉，從頭算，光化學(xué)

關(guān)鏈詞：硼碳基絡(luò)合物，σ-π配鏈，紅外光解離光譜，理論計(jì)算

鄰碘甲苯分子光解動(dòng)力學(xué)的飛秒時(shí)間分辨質(zhì)譜研究..............53劉志明，王艷梅，胡春龍，龍金友，張冰?(中國(guó)科學(xué)院武漢物理與數(shù)學(xué)研究所，波譜與原子分子物理國(guó)家重點(diǎn)實(shí)驗(yàn)室，武漢430071)

關(guān)鏈詞：鄰碘甲苯，光解，解離時(shí)間，飛秒時(shí)間分辨質(zhì)譜

高分辨率初始光電子能譜由真空紫外激光速度—映射圖像的方法... ..............................................................59律洲，高蕻，徐運(yùn)濤，楊磊，林周成，Yanice Benitez，伍灼耀?(加州大學(xué)戴維斯分?；瘜W(xué)系，戴維斯95616)

F管轄，這是半經(jīng)典預(yù)測(cè)值?6.1√ F的一半.我們還測(cè)量C6H5Cl和C3H5的真空紫外光能量的真空紫外VMI-PE譜接近其電離初始值.在VUV-VMI-PE測(cè)量中觀察到的陽(yáng)離子振動(dòng)譜和振動(dòng)級(jí)數(shù)，.真空紫外VMI-TPE可以實(shí)現(xiàn)更高的實(shí)驗(yàn)靈敏度和類似真空紫外PFI-PE測(cè)量的能量分辨率，使真空紫外VMITPE法成為高分辨率真空紫外PFI-PE測(cè)量一個(gè)很好的替代.

關(guān)鏈詞：光電離，初始光電子，速度-地圖成像，自由基

交叉?zhèn)鞑?gòu)型的和頻振動(dòng)光譜.................................70付力a，陳順利a,b，干為b，王鴻飛a?(a.美國(guó)能源部西北太平洋國(guó)家實(shí)驗(yàn)室環(huán)境分子科學(xué)研究所，里奇蘭99352；b.中國(guó)科學(xué)院新疆理化技術(shù)研究所環(huán)境科學(xué)和技術(shù)實(shí)驗(yàn)室，烏魯木齊830011)

Chin.J.Chem.Phys.Vol.29，No.1

化學(xué)物理學(xué)報(bào)，第29卷，第1期

這一交叉實(shí)驗(yàn)構(gòu)型的潛在應(yīng)用包括表面科學(xué)、材料科學(xué)、基礎(chǔ)催化科學(xué)以及低溫下的分子科學(xué)等方面.

關(guān)鏈詞：和頻產(chǎn)生，振動(dòng)光譜，共向傳播，反向傳播，交叉?zhèn)鞑?/p>

過(guò)渡金屬羰基化合物Mn(CO)5Br和Re(CO)5Br結(jié)構(gòu)與動(dòng)力學(xué)的超快光譜.....................................................81封敏軍a,b，楊帆a，王建平a?(a.中國(guó)科學(xué)院化學(xué)研究所北京分子科學(xué)國(guó)家實(shí)驗(yàn)室，分子反應(yīng)動(dòng)力學(xué)實(shí)驗(yàn)室，北京100190；b.中國(guó)科學(xué)院大學(xué)，北京100149)

關(guān)鏈詞：過(guò)渡金屬羰基化合物，瞬態(tài)紅外光譜，振動(dòng)弛豫，非諧性

金屬/水界面振動(dòng)光譜的等離基元場(chǎng)增強(qiáng).......................87劉志華，徐倩，劉韡韜?(復(fù)旦大學(xué)物理系，應(yīng)用表面物理國(guó)家重點(diǎn)實(shí)驗(yàn)室，微納光子結(jié)構(gòu)教育部重點(diǎn)實(shí)驗(yàn)室，先進(jìn)微結(jié)構(gòu)協(xié)同創(chuàng)新中心，上海200433)

關(guān)鏈詞：金屬-水界面，表面等離子體激發(fā)，光學(xué)異常透射

安息香籠化合物光化學(xué)反應(yīng)的時(shí)間分辨紅外光譜................91代小娟a，余友清a，劉坤輝b?，蘇紅梅a,b?(a.中國(guó)科學(xué)院化學(xué)研究所，北京分子科學(xué)國(guó)家實(shí)驗(yàn)室(籌)，北京100190；b.北京師范大學(xué)化學(xué)學(xué)院，北京100875)

利用激光濺射原子束裝置結(jié)合時(shí)間切片速度成像技術(shù)對(duì)于金屬態(tài)-態(tài)反應(yīng)動(dòng)力學(xué)的相關(guān)研究........................................99董常武，劉嘉興，李芳芳，王鳳燕?(復(fù)旦大學(xué)化學(xué)系，化學(xué)能源材料協(xié)同創(chuàng)新中心，上海200433)

關(guān)鏈詞：時(shí)間切片速度成像，交叉分子束，激光濺射，金屬原子反應(yīng)動(dòng)力學(xué)

甲醇在二氧化鈦上的光化學(xué)性質(zhì)與表面結(jié)構(gòu)的相關(guān)性..........105郝群慶a，王志強(qiáng)a，毛新春b，周傳耀a?，戴東旭a，楊學(xué)明a?(a.中國(guó)科學(xué)院大連化學(xué)物理研究所分子反應(yīng)動(dòng)力學(xué)國(guó)家重點(diǎn)實(shí)驗(yàn)室，大連

關(guān)鏈詞：二氧化鈦，電子激發(fā)態(tài)，雙光子光電子能譜，光催化氧化速率

鏈長(zhǎng)-鏈角和Radau坐標(biāo)下哈密頓算符在傅里葉基組表象下的厄米性...........................................................112于德權(quán)a，黃鶴a,b，Gunnar Nymanc，孫志剛a,d?(a.中國(guó)科學(xué)院大連化學(xué)物理研究所分子反應(yīng)動(dòng)力學(xué)國(guó)家重點(diǎn)實(shí)驗(yàn)室，大連116023；b.遼寧師范大學(xué)物理與電子技術(shù)學(xué)院，大連116029；c.瑞典哥德堡大學(xué)化學(xué)學(xué)院，哥德堡；d.中國(guó)科學(xué)與技術(shù)大學(xué)，量子信息與量子科技前沿協(xié)同創(chuàng)新中心，合肥230026)

關(guān)鏈詞：哈密頓量，快速傅里葉變換，傅里葉基組，含時(shí)波包方法，吸收光譜

TiGen?(n=7～12)團(tuán)團(tuán)簇的光電子能譜及密度泛函理論研究...123鄧曉嬌，孔祥玉，徐西玲，許洪光?，鄭衛(wèi)軍?(中國(guó)科學(xué)院化學(xué)研究所，北京分子科學(xué)國(guó)家實(shí)驗(yàn)室(籌)，分子反應(yīng)動(dòng)力學(xué)國(guó)家重點(diǎn)實(shí)驗(yàn)室，北京100190)

關(guān)鏈詞：光電子能譜，密度泛函理論，鍺團(tuán)簇

拉曼除譜原位測(cè)量水溶液中蛋白質(zhì)的酰胺A譜帶...............129湯城騫a，林珂b?，周曉國(guó)a,c，劉世林a?(a.中國(guó)科學(xué)技術(shù)大學(xué)合肥微尺度物質(zhì)科學(xué)國(guó)家實(shí)驗(yàn)室，化學(xué)物理系，合肥230026；b.西安電子科技大學(xué)物理與光電工程學(xué)院，西安710071；c.量子信息與量子科技前沿協(xié)同創(chuàng)新中心，合肥230026)

關(guān)鏈詞：拉曼除譜，酰胺A譜帶，原位，蛋白質(zhì)，水

高分辨的一氧化二氮光解離實(shí)驗(yàn)研究..........................135俞盛銳a,b，袁道福a，陳文韜a，謝婷a，王思雯a，楊學(xué)明a,b?，王興安a,c?(a.中國(guó)科學(xué)技術(shù)大學(xué)化學(xué)與材料科學(xué)學(xué)院化學(xué)物理系物理化學(xué)高等研究中心，合肥230026；b.中國(guó)科學(xué)院大連化學(xué)物理研究所分子反應(yīng)動(dòng)力學(xué)國(guó)家重點(diǎn)實(shí)驗(yàn)室，大連116023；c.能源材料化學(xué)協(xié)同創(chuàng)新中心，合肥230026)

Chin.J.Chem.Phys.Vol.29，No.1

化學(xué)物理學(xué)報(bào)，第29卷，第1期

子在134.20、135.20和136.43nm波長(zhǎng)下的真空紫外光解動(dòng)力學(xué).實(shí)驗(yàn)中通過(guò)采集解離產(chǎn)物O(1SJ=0)的離子影像來(lái)研究O(1SJ=0)+N2(X1Σ+g)這一解離通道.從各個(gè)波長(zhǎng)下的實(shí)驗(yàn)影像可獲得產(chǎn)物N2(X1Σ+g)的振動(dòng)態(tài)分辨的結(jié)構(gòu)，進(jìn)而得到產(chǎn)物的總平動(dòng)能譜和產(chǎn)物N2的振動(dòng)態(tài)布居.實(shí)驗(yàn)結(jié)果表明在實(shí)驗(yàn)的光解波長(zhǎng)下，產(chǎn)物N2(X1Σ+g)主要布居在v=2和v=3.此外，還得到了產(chǎn)物N2的振動(dòng)態(tài)分辨的各向異性參數(shù)β，從中發(fā)現(xiàn)產(chǎn)物N2的β值在三個(gè)解離波長(zhǎng)下均表現(xiàn)出相似的特征，即隨著振動(dòng)量子數(shù)的增大，β值從趨近于2逐漸減小至1.4.這一現(xiàn)象表明低振動(dòng)態(tài)產(chǎn)物是通過(guò)一個(gè)以平行躍遷解離為主的解離過(guò)程產(chǎn)生的，而高振動(dòng)態(tài)的產(chǎn)物來(lái)自于一個(gè)更加彎曲的中間構(gòu)型的解離.此推論與在平動(dòng)能譜中所見到的最強(qiáng)轉(zhuǎn)動(dòng)態(tài)布居隨著振動(dòng)量子數(shù)的增大而出現(xiàn)的位移是相一致的.

關(guān)鏈詞：一氧化二氮，離子成像，真空紫外，光解

吡啶離子液體與水混合體系中蒽醌-2-磺酸鈉的激光閃光光解機(jī)理.. .............................................................140朱光來(lái)a?，張良偉a，劉艷成b，崔執(zhí)鳳a，許新勝a，吳國(guó)忠b?(a.安徽師范大學(xué)原子與分子物理研究所，蕪湖241000；b.中國(guó)科學(xué)院上海應(yīng)用物理研究所，上海201800)

中，3AQS?分別與H2O和[BPy][BF4]的反應(yīng)是一對(duì)競(jìng)爭(zhēng)反應(yīng).還發(fā)現(xiàn)在高濃度的離子液體環(huán)境下，體系的整體反應(yīng)速率會(huì)減弱.

關(guān)鏈詞：激光閃光光解，蒽醌-2-磺酸鈉，離子液體，瞬態(tài)吸收，奪氫基于熒光非共線光參量放大光譜技術(shù)的溶劑化動(dòng)力學(xué)研究中的光譜矯正........................................................147黨偉a,b，白晶晶a，張連水a(chǎn)?，翁羽翔b?(a.河北省光電信息材料重點(diǎn)實(shí)驗(yàn)室，河北大學(xué)物理科學(xué)與技術(shù)學(xué)院,保定071002；b.中國(guó)科學(xué)院物理研究所軟物質(zhì)物理重點(diǎn)實(shí)驗(yàn)室，北京100190)

關(guān)鏈詞：原子阱痕量分析，氣相色譜分離，放射性惰性氣體

Supporting Information

Spectrum correction in the study of solvation dynamics by

fluorescence non-collinear optical parametric amplification

spectroscopy

Wei Danga,b, Jing-Jing Baia, Lian-Shui Zhanga?, Yu-Xiang Wengb*

a Hebei Key Lab of Optic-electronic Information and Materials, College of Physics Science and Technology,

Hebei University, Wusi East 180, Baoding, 071002, China

bKey Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, No.8, 3rd

South Street, Zhongguancun, Beijing, 100190, China

E-mail address: zhangls@hbu.edu.cn; yuxiangweng@iphy.ac.cn

The detailed description of FNOPAS setup

The setup of FNOPAS is schematically presented In Figure S1. A laser pulse(150 fs, 300 uJ , at 800 nm and 1 kHz repetition rate) is split into two beams with a 1:1 energy ratio. The reflected fundamental beam passes through a delay line, then an inverted telescope consisting of a lens pair L2/L3 with a focal length of +200 mm and - 75 mm, respectively. This fundamental beam is frequency doubled to 400 nm in a BBO crystal (cutting angle 29.2°) of 1 mm thickness. This second-harmonic(SH) generation beam works as both the pump source for parametric amplification process and the gating beam of fluorescence photons. The transmitted fundamental beam is also frequency doubled to 400 nm in another BBO crystal (1mm, cutting angle 29.2°). After being focused by a lens L1(f=75 mm), this SH excites DCM ethanol solution (3×10-4mol/L). To suppress the population of triplet state, the solution is continuously stirred by a tiny magnetic bar during the measurement. The fluorescence from DCM solution is collected and imaged onto a 2 mm thick BBO crystal (cutting angle 31.5°) by a lens L4(f= 38.1 mm). A 500 nm long pass filter (F1) is placed to remove the scattered light of excitation beam. The fluorescence is gated and amplified through non-collinear optical parametric amplification process in the BBO crystal. The amplified fluorescence is recorded as the time-resolved spectrum by a CCD spectrograph. The details of data acquiring procedure have been given in the reference 1. Before data analysis, the acquired transient fluorescence spectra should be corrected with the curve of spectral gain. Due to transmission through ethanol solution, sample cell windows, lenses and the filter, fluorescence photons are subjected to group velocity dispersion (GVD). Thus GVD correction for the transient fluorescence spectra should be carried out after the spectral gain correction.

Fig.S1 The setup of femtosecond time-resolved fluorescence non-collinear optical parametric amplification spectroscopy. BS: 1:1 beam splitter; L1-L6: lens; F1: 500 nm long pass filter; 400nm HR: high reflectivity mirror at 400 nm; CCD: CCD spectrograph.

關(guān)鏈詞：瞬態(tài)熒光光譜，溶劑化動(dòng)力學(xué)，非共線光參量放大，光譜矯正

從環(huán)境樣品中分離氬氣和氪氣用于放射性惰性氣體探測(cè)........151涂樂(lè)義a，楊國(guó)民a，張向陽(yáng)a,b，胡水明a?(a.中國(guó)科學(xué)技術(shù)大學(xué)合肥微尺度物質(zhì)國(guó)家實(shí)驗(yàn)室(籌)，合肥230026；b.中國(guó)地質(zhì)科學(xué)院水文地質(zhì)環(huán)境地質(zhì)研究所，石家莊050061)

Corresponding author.