CAJ | 학술논문

利用高分辨率瞬时激光光谱技术，研究了 H2（1，1）与CO2碰撞中的能量转移。受激拉曼泵浦把 H2（0，1）激发到 H2（1，1）能级，H2（1，1）与 CO2碰撞，使 CO2的振转态得到布居，通过泛频吸收得到 CO2（0000）和（0001）的转动态分布，测量 H2（0，1）和 H2（1，1）的CARS（相干反斯托克斯拉曼散射）谱，得到这二个能级布居数密度之比，而 H2（0，1）密度通过在池温300 K下 H2（v＝0）的转动Boltzmann分布得到。碰撞转移速率系数由一个速率方程得到，对于CO2（0000）J＝48～76，速率系数ktr从（3．9±0．8）×10-11单调递增到（1．4±0．3）×10-10 cm3·molecule-1·s-1，而对于（0001）J＝5～33，速率系数均在（4．3±0．9）×10-12 cm3·molecule-1·s-1附近。随 H2（1，1）的激发，在0．5μs 内测量CO2（0000）和（0001）原生态的转动布居，得到玻尔兹曼转动温度Trot，对于（0000）态，有Trot＝1100 K，对于（0001）态有Trot＝310 K，与池温接近。利用泛频吸收线的多普勒增宽测量，得到CO2各转动态的实验室平移温度Ttran和质心平移温度Trel ，对于（0000）J＝48和76，Trel分别为454和1532 K，平动能平均变化在231～1848 cm-1之间，而对于（0001）J＝5～33，平均平动能基本无变化。
이용고분변솔순시격광광보기술，연구료 H2（1，1）여CO2팽당중적능량전이。수격랍만빙포파 H2（0，1）격발도 H2（1，1）능급，H2（1，1）여 CO2팽당，사 CO2적진전태득도포거，통과범빈흡수득도 CO2（0000）화（0001）적전동태분포，측량 H2（0，1）화 H2（1，1）적CARS（상간반사탁극사랍만산사）보，득도저이개능급포거수밀도지비，이 H2（0，1）밀도통과재지온300 K하 H2（v＝0）적전동Boltzmann분포득도。팽당전이속솔계수유일개속솔방정득도，대우CO2（0000）J＝48～76，속솔계수ktr종（3．9±0．8）×10-11단조체증도（1．4±0．3）×10-10 cm3·molecule-1·s-1，이대우（0001）J＝5～33，속솔계수균재（4．3±0．9）×10-12 cm3·molecule-1·s-1부근。수 H2（1，1）적격발，재0．5μs 내측량CO2（0000）화（0001）원생태적전동포거，득도파이자만전동온도Trot，대우（0000）태，유Trot＝1100 K，대우（0001）태유Trot＝310 K，여지온접근。이용범빈흡수선적다보륵증관측량，득도CO2각전동태적실험실평이온도Ttran화질심평이온도Trel ，대우（0000）J＝48화76，Trel분별위454화1532 K，평동능평균변화재231～1848 cm-1지간，이대우（0001）J＝5～33，평균평동능기본무변화。
Energy transfer in H2 (1 ,1 )+CO2 collisions was investigated using high resolution transient laser spectroscopy.Rota-tional state selective excitation ofν= 1 for rotational level J= 1 was achieved by stimulated Raman pumping.Energy gain into CO2 resulting from collisions with H2 (1,1)was probed using transient absorption techniques,Distributions of nascent CO2 rota-tional populations in both the ground (0000)state and the vibrationally excited (0001)state were determined from overtone ab-sorption measurements.Translational energy distributions of the recoiling CO2 in individual rovibrational states were determined through measurement of Doppler-broadened transient line shapes.A kinetic model was developed to describe rates for appearance of CO2 states resulting from collisions with H2 (1 ,1 ).From scanned CARS(coherent anti-stokes raman scattering)the spectral peaks population ratio n0/n1 was obtained,where n0 and n1 represent the number densities of H2 at the levels (0,1)and (1,1), respectively.Using rotational Boltzmann distribution of H2 (ν= 0)at 300 K,n1 was yielded.Values for rate coefficients were ob-tained using data for CO2(0000)J= 48 to 76 and CO2(0001)J= 5 to 33.The rate coefficients derived from appearance of the (0000)state have values of ktr= (3. 9±0. 8)×10-11 cm3 ·molecule-1 ·s-1 for J= 48 and ktr= (1. 4±0. 3)×10-10 cm3 ·mole-cule-1 ·s-1 for J= 76,with a monotonic increase for the higher J states.For the (000 1)state,values of ktr remain fairly con-stant at ktr= (4. 3±0. 9)×10-12 cm3 ·molecule-1 ·s-1 .Rotational populations for the nascent CO2 states were measured at 0. 5μs following excitation of H2 .The transient population for each state was fit using a Boltzmann rotational distribution.The CO2 (000 0)J= 48~76 rotational states were populated substantially relative to the initial 300 K CO2 distributions,and the distribu-tion is described by Trot.The excited (000 1 )state has Trot= 310 K.The center-of-mass translational temperatures for the (0000)state are all much greater than 300 K,with Trel= 1 532 K for J= 76.In contrast,transient line profiles for the J= 5~33 levels of excited (000 1)state do not show any broadening above the initial 300 K distributions,indicating that excitation to the (000 1)state is not accompanied by translational energy change.