高位振动态RbH(X~1∑~+,v"≥15)与CO_2碰撞转移中的能量相关性
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摘要
研究了高位振动态RbH(X~1∑~+,v″=15～21)与CO_2碰撞转移过程.脉冲激光激发RbH至高位态,利用激光感应荧光光谱(LIF)得到RbH(X~1∑~+,v″)与CO_2的猝灭速率系数k_(v″)(CO_2),k_(v″=21)(CO_2)=2.7k_(v~n=15)(CO_2).利用激光泛频光谱技术,测量了CO_2(00~0,J)高转动态分布,得到了转动温度,从而获得了平均转动能和转动能的变化<△E_(rot)>,发现<△E_(rot)>_(v″=21)≈2.9<△E_(rot)>_(v″=15).对于v″=16,证实了振动—振动能量转移的4-1近共振过程.在一次碰撞条件下,通过速率方程分析,得到RH(v″)-CO_2振转速率系数.对于v″=15,J=32-48,速率系数在1.25-0.33×10~(-13)cm~3s~(-1).之间;对于v″=21,速率系数在2.47-1.53×10~(-13)cm~3s~(-1)之间,其能量相关性是明显的.
The energy transfer of highly vibrational excited RbH through collision with CO_2 is investigated using the laser spectroscopy technique.RbH is formed by the Rb(7s) + H_2 reaction.The pulse laser prepares RbH in the highly vibrational levels.LIF is used to detect collisionally relaxed RbH,The relaxation rate coefficient of RH(v″=21) with CO_2 is up to 2.7 times lager that of RH(v″=15).Relaxation of RH(v″) with H_2 is also investigated.The observed collisional relaxation rate coefficient of H_2 are bigger that those of CO_2.Energy gain into CO_2 resulting from collisions with excited RH is probed using laser overtone spectroscopy technique.Distributions of nascent CO_2.rotational population in the ground (00°0) state are determined.The rotational temperatures are obtained.Based on rotational temperatures, the average change in the CO_2 rotational energy <△E_(rot)> is yielded.<△E_(rot)>_(v″=21)≈2.9 <△E_(rot) >(v″15) has been found.For v″=16,vibration-vibration energy transfer of the 4-1 near-resonant is observed. Under single-collision conditions,The rate coefficientk~(J″) v for collisions of RH(v″) with CO_2 have been determined using a simple kinetic model.For v″=15,the rate coefficients for CO_2 J = 32～48 are 1.25～0.33×10~(-13)cm~2s~(-1).For v" = 21,the the rate coefficients for CO_2 J = 32—48 are 2.47—1.53×10~(-13)cm~3s~(-1).Rate coefficients for the appearance of high-J CO_2 states show comparable energy dependence.
The energy transfer of highly vibrational excited RbH through collision with CO_2 is investigated using the laser spectroscopy technique.RbH is formed by the Rb(7s) + H_2 reaction.The pulse laser prepares RbH in the highly vibrational levels.LIF is used to detect collisionally relaxed RbH,The relaxation rate coefficient of RH(v″=21) with CO_2 is up to 2.7 times lager that of RH(v″=15).Relaxation of RH(v″) with H_2 is also investigated.The observed collisional relaxation rate coefficient of H_2 are bigger that those of CO_2.Energy gain into CO_2 resulting from collisions with excited RH is probed using laser overtone spectroscopy technique.Distributions of nascent CO_2.rotational population in the ground (00°0) state are determined.The rotational temperatures are obtained.Based on rotational temperatures, the average change in the CO_2 rotational energy <△E_(rot)> is yielded.<△E_(rot)>_(v″=21)≈2.9 <△E_(rot) >(v″15) has been found.For v″=16,vibration-vibration energy transfer of the 4-1 near-resonant is observed. Under single-collision conditions,The rate coefficientk~(J″) v for collisions of RH(v″) with CO_2 have been determined using a simple kinetic model.For v″=15,the rate coefficients for CO_2 J = 32～48 are 1.25～0.33×10~(-13)cm~2s~(-1).For v" = 21,the the rate coefficients for CO_2 J = 32—48 are 2.47—1.53×10~(-13)cm~3s~(-1).Rate coefficients for the appearance of high-J CO_2 states show comparable energy dependence.
引文
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[4]Mack J A,Mikulecky K,Wodtk A M.Resonant vibration - vibration energy transfer between highly vibrationally excited O_(X~3∑_g~-,v=15～26) and CO_2,N_2O,N_2,and O_3[J].J.Chem.Phys.,1996, 105(10):4105
[5]Yamasaki K,Fuji H,Watanabe S,et al.Eflcient vibrational relaxation of O_2(X~3∑_g~-,v= 8) by collisions with CF_4[J].Phys.Chem.Chem.Phys., 2006,8:1936
[6]Watanabe S,Fuji H,Kohguchi H,et al.Kinetic study of vibrational energy transfer from a wide range of vibrational levels of O_2(X~3∑_g~-,v= 6～12) to CF_4~+[J].J.Phys.Chem.A,2008,112:9290
[7]Yuan L W,Du J,Mullin A S.Energy-dependent dynamics of large-AE collisions:highly vibrationally excited azulene(E=20390 and 38580 cm~(-1) with CO_2 [J].J.Chem.Phys.,2008,129:014303
[8]Michael C A,Mullin A S,Flynn G W.Long- and short-range interactions in the temperature dependent collisional excitation of the antisymmetric stretching CO_2(00°1) Level by highly vibrationally excited pyrazine[J].J.Chem.Phys.,1995,102:6682
[9]Fan L H,Chen J J,Lin Y Y,et al.Reaction of Rb (5~2D,7~2S) with H_2[J].J.Phys.Chem.A,1999, 103:1300
[10]Lucchesini A,Gozzini S.Diode laser overtone spectroscopy of CO_2 at 780 nm[J].J.Quant.Spectrosc. Radiat.Transf.,2005,96:289
[11]Zhang L P,Cai Q,Luan N N,et al.Collsional energy transfer between highly excited vibrational levels of K_2(1~∑_u~+,v= 46～61) and H_2[J].J.At. Mol.Phys.,2011,28(6):1056(in Chinese)[张利平,蔡勤,栾楠楠,等.Kz高激发振动能级1~∑_u~+(v =46～61)与H_2间的碰撞能量转移[J].原子与分子物理学报,2011,28(6):1056]
[12]Stwalley W C,Zemke W T,Yang S C.Spectroscopy and structure of the alkali hydride diatomic molecules and their ions[J].J.Phys.Chem.Ref.Data, 1991,20(1):153