OPTICAL-OPTICAL DOUBLE-RESONANCE EXCITATION SPECTRA OF THE (6d)1Πg, (7d)1Πg HIGH-LYING RYDBERG STATES IN Na2

Two ¹Π_g states of Na₂ for v≤13 have been observed by using optical-optical double resonance (OODR) fluorescence excitation spectroscopy. The intermediate levels in B¹Π_u state are identified by the numerical calculations with the molec-ular constants for B¹Π_u←X¹Σ_g⁺ transitions and confirmed by the complemen-tary A¹Σ_g⁺←X¹Σ_g⁺ polarization spectra. Absolute vibrational numberings of the (6d)¹Π_g and (7d)¹Π_g states are determined by comparing the experimental OODR excitation intensities with the simulated Franck-Condon factors. The Dnnham coef-ficients and the Rydberg-Klein-Rees (RKR) potential energy curves of the (6d)¹Π_g, (7d)¹Π_g states are reported.     

C2H221分子转动角动量定向分布(Orientation)及其碰撞弛豫和转移

利用圆偏振激光受激Raman抽运,以 C₂H₂分子为样品选择性地制备了它的电子基态单一转动态(X¹Σ⁺_g,ν″₂＝1,J″的角动量定向布居(orientation)．并从圆偏振紫外激光诱导的A¹A_u(ν′₃＝1)←X¹Σ⁺_g(ν″₂＝1)的荧光（谱）,直接测定了 C₂H₂(X¹Σ^＋_g,ν″₂＝1,J″＝4,7,8,…,13）的角动量定向布居值．从时间分辨的荧光信号谱测定了角动量定向布居的碰撞弛豫速率常数,同时还研究了由各初始激励的转动态向其他邻近转动态碰撞诱导的角动量定向布居转移． 关键词：     

用新公式研究K2分子部分电子态的离解能

本文使用孙卫国等人提出的基于微扰理论的代数方法（AM）,研究了碱金属K₂分子的五个电子态X¹∑_g⁺、a³∑_u⁺、O_g^-、B¹∏_u和3³∏_g的离解能;然后使用作者最近提出的新公式计算了这些电子态的离解能,并分别与实验值进行了比较.计算结果表明:使用新公式得到的分子离解能与实验值非常吻合.而对那些还没有离解能实验数据的电子态,该公式提供了一种推测其离解能的理论计算方法.     

高位振动态RbH（X1∑+,v"≥15）与CO2碰撞转移中的能量相关性

研究了高位振动态RbH（X¹∑⁺,v″=15～21）与CO₂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（X¹∑⁺,v″）与CO₂的猝灭速率系数k_v″（CO₂）,k_v″=21（CO₂）=2.7k_vⁿ=15（CO₂）.利用激光泛频光谱技术,测量了CO₂（00⁰,J）高转动态分布,得到了转动温度,从而获得了平均转动能rot>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″）-CO₂振转速率系数.对于v″=15,J=32-48,速率系数在1.25-0.33×10^-13cm³s^-1.之间;对于v″=21,速率系数在2.47-1.53×10^-13cm³s^-1之间,其能量相关性是明显的.     

H2(X1∑g+)—H2(E1∑g+)系统的相互作用

采用显含电子对相关坐标的波函数,在微扰论的框架下计算了E^l∑_g⁺态氢分子与基态氢分子取cross构型时的中长程相互作用。结果表明,该相互作用在分子间距6.5α₀附近存在着一个活化能势垒,在4.5α₀附近显示出较强的化学键行为。 关键词：     

氨分子在000和201带的选择光离解

本文利用脉冲紫外激光(UV)选择激发氨分子到?¹A″₂电子激发态的两个最低振动能级ν′₂=0和ν′₂=1(ν₂振动),然后检测新生态H原子的飞行谱(TOF),研究了氨分子的光碎片动力学。光谱证实了最近所测的离解能D₀⁰(H-NH₂)=4.645eV;绝大多数生成的NH₂(X²B₁)基处于非振动激发,但是具有围绕a惯性轴的高度转动激发。通过NH₃(?)的ν′₂=1光离解产生的NH₂(X)基具有较高的内部激发,并且显示了在N=K_a转动能级上的反转布居。 关键词：     

钙钛矿型晶体A(B1/31B2/32)O3中的有序-无序相变

本文利用原子集团变分方法,讨论了A⁺²(B_1/3⁺²B_2/3⁺⁵)O₃系统中有序-无序相变,指出在此系统中相互作用能参数对形成(B_2/3⁺²B_1/3⁺⁵)_1/2:B_1/2⁺⁵=1:1的混合型有序畴和B_{1/3关键词：}     

C_2^+ (X^4 Σ_g^-,1^4 Σ_u^+)离子体系解析势能函数、光谱常数和振动能级研究

采用多参考组态相互作用(MRCI)方法,结合aug-cc-pV6Z(AV6Z)基组,计算了C₂⁺(X⁴Σ_g^-,1⁴Σ_u⁺)的势能曲线,计算过程中考虑了Davidson修正和相对论效应,并将结果外推至完备基组(CBS)的极限.基于得到的单点能量,用最小二乘法方法进行了Murrell-Sorbie函数拟合,得到了势能函数解析式(APEF).基于APEF,计算了C₂⁺(X⁴Σ_g^-,1⁴Σ_u⁺)离子体系的离解能D_e,平衡核间距R_e,光谱常数ω_e,ω_eχ_e,B_e,α_e,结果与实验和其他理论计算值符合...     

K2分子23∏g—13∑u+漫射谱强度的碰撞诱导增强效应

用4415.6?CW激光线获得了5730?附近的K₂分子2³∏_g—1³∑_u⁺漫射荧光谱。实验研究了缓冲气体Ar气压强P对漫射谱峰值强度I_diff的碰撞诱导增强效应。用稳态碰撞模型描述了C¹∏_u—2³∏_g间的能量转移过程,推导出了I_diff-P函数关系,对实验数据进行了令人满意的拟合。这种拟合表明:适当变更实验装置,利用本文模型可以得到C¹∏_u—2³∏_g间的能级交叉速率和碰撞诱导转移速率。 关键词：     

CH2Br2的同步辐射光电离研究:10—12eV范围内CH2Br2的振动自电离态

报道在超声射流冷却条件下用同步辐射ＶＵＶ光源研究ＣＨ₂Ｂｒ₂的振动自电离结构．根据测量的１０５—１２３ｎｍ范围内母体离子（ＣＨ₂Ｂｒ₂⁺）的光电离产率曲线，获得ＣＨ₂Ｂｒ₂的绝热电离势为１０.２３±０.０１ｅＶ．ＣＨ₂Ｂｒ₂⁺的最低三个电子激发态，即Ａ（²Ａ₂），Ｂ（²Ｂ₁），Ｃ（²Ａ₁）分别位于１０.７８±０.０１ｅＶ，１１.２０±０.０１ｅＶ和１１.２７±０.０１ｅＶ．在１１５.０１—１２１.１５ｎｍ范围内，观察到ＣＨ₂Ｂｒ₂自电离峰叠加在若干台阶结构上，台阶平均宽度为７１６.８±４０.０ｃｍ^-1，对应于ＣＨ₂Ｂｒ₂⁺（Ｘ²Ｂ₂）中Ｂｒ-Ｃ-Ｂｒ反对称的伸缩振动（ｖ₉），所有的峰均归属为收敛于ＣＨ₂Ｂｒ₂⁺（Ｘ²Ｂ₂，ｖ⁺）振动能级的ｎｓ，ｎｐ和ｎｄ自电离Ｒｙｄｂｅｒｇ态．此外，对ＣＨ₂Ｂｒ₂光解离电离产生离子型自由基ＣＨ₂Ｂｒ⁺（Ｘ）的光电离产率曲线的结构也进行了归属 关键词：     

α-Al2O3单晶中Fe3+离子的电子顺磁共振

本文对α-Al₂O₃单晶体中Fe³⁺离子在室温下,X波段进行了电子顺磁共振研究,发现Fe³⁺离子实际上占据四种磁性不等价晶位。在同一氧离子层间的两种晶位上的Fe³⁺离子具有相同的自旋哈密顿参量,而不同氧离子层间的晶位上的Fe³⁺离子具有不同的自旋哈密顿参量,两种自旋哈密顿参量为:(1)g_‖=2.001,g_⊥=2.003,D=1679 关键词：     

克里奇中间体CH2OO与CF3CF=CF2反应的动力学研究

本文使用OH激光诱导荧光方法研究了结构最简单的克里奇中间体CH₂OO和CF₃CF=CF₂的反应动力学. 在压强为10 Torr条件下,测量了温度在283,298,308和318 K的反应速率常数,分别为(1.45±0.14)×10^-13,(1.18±0.11)×10^-13,(1.11±0.08)×10^-13和(1.04±0.08)×10^-13 cm³·molecule^-1·s^-1. 根据阿伦尼乌斯方程,获得该反应的活化能为(-1.66±0.21) kcal/mol. 在6.3∽70 torr压力范围内,未观察到该反应的速率常数存在压力相关.     

The interacting states (020), (100), and (001) of H217O and H218O

A fit of about 350 rotational levels of the (020), (100), and (001) vibrational states has been performed for H₂¹⁷O as well as for H₂¹⁸O leading to the determination of 51 rotational and coupling constants for each isotopic species. The Fermi-type interaction and the two Coriolis-type interactions have been taken into account by appropriate rotation-vibration operators and the v-diagonal part of the Hamiltonian is, for each vibrational state, a Watson-type Hamiltonian. The results are very satisfactory since 87% of the experimental levels are reproduced within 15 × 10^?3 cm^?1.     

High precision spectrum of N2O at 4.5 μm and determination of molecular constants for the ν3 and the (ν2 + ν3 − ν2) bands

A high precision wavenumber calibration has been achieved for the spectrum of N₂O at 4.5 μm. The values of the wavenumbers are reported for the (00°1-00°0) and for the (01¹1-01¹0) transitions. A new set of molecular constants is given for the upper and lower levels of these two transitions. In particular, the value of the H constant for the ground state (?2.02 ± 0.4) × 10^?13 cm^?1 determined in this work is significantly different from previous results.     

态—态振动能量跃迁的时间分辨研究(Ⅰ)——碘分子的自碰撞过程

本文介绍了采用可调脉冲激光技术和时间分辨色散荧光方法研究态-态碰撞动力学的实验过程。在实验中直接观测了处于电子振动激发态B³Π_ou⁺(v＇=19)的碘分子在自碰撞事件中朝相邻振动态跃迁的衰变过程,得到态—态振动跃迁速率常数,k_v(19→18)=(2.21±0.33)×10^-11cm³s^-1mol^-1和k_v(19 关键词：     

The absorption spectrum of CO2 around 7740 cm-1

Absolute intensities of the vibration-rotation lines of the CO₂ 401_II←000 band 7734 cm^-1 are measured under high-resolution, low-pressure conditions by use of a White-type 25-m base-path, absorption cell together with a 5-m Czerny-Turner spectrometer. The total band intensity S_B, the purely vibrational transition moment

, and the vibration-rotation interaction constant ζ are calculated from the intensity measurements. The values obtained for these parameters are S_B(401_II) = (7.06±0.07) × 10^-5 cm^-2 atm^-1_293°K,

= (3.08±0.03)×10^-5 debye, and ζ = (2.5±0.5)×10^-4. The intensity of the associated “hot band” 411_II←010 is also determined and found to be S_B(411_II←010) = (0.53±0.02)×10^-5 cm^-2 atm^-1_293°K.     

Hydrogen diffusion constants in stainless steel and Pd60Ag40 alloy, and permeability of diaphragms made of these metals

Hydrogen permeability through diaphragms made of 12X18H12T stainless steel and Pd₆₀Ag₄₀ alloy under electrolytic hydrogen saturation has been studied with an electrolytic cell with a vacuum chamber. Hydrogen diffusion constants D _H = 3.86 × 10⁻¹⁰ cm² s⁻¹ for stainless steel and D _H = 4.36 × 10⁻⁸ cm² s⁻¹ for Pd₆₀Ag₄₀ alloy have been determined at a temperature of 40°C using the Berrer relations.     

Shock-tube determination of absorption cross sections and A2Δ − X2Π band transition moments of SiH

The overall absorption cross sections and electronic transition moments of the A²Δ ? X²Π band system of SiH have been determined by using an absorption technique with a shock tube at temperatures of 2600–3800 K over the wavelengths of 150–650 nm. Absorption cross sections are shown to be dominated by continua. The possible contributions to the overall cross sections by a low-lying ⁴Σ^- and a high-lying ⁴Σ^- state are discussed. At 200, 228, 340, 405, and 550 nm, the continuum cross sections are (2.9±1.0)×10^-17, (2.0±0.5)×10^-17, (3.2±0.6)×10^-18, (3.8±0.6)×10^-18, and (1.8±0.8)×^-18cm², respectively. The overall emission intensity and the Si+H→SiH+hv radiative recombination rate are (6.7± 2.3)×10^-35(3500/T)^0.7(Si)(H) watt-cm^-3 and (1.3±0.4)×10^-17(3500/T)^1.1(Si)(H) cm^-3-s^-1, respectively. The A ? X transition moments are 0.12±0.04a.u. for the (0, 0) and (1, 1) bands. The intensity of each branch in the A ? X (0, 0) band follows approximately the prediction based on the Hönl-London factors of Kovacs. The data are applied to the study of the flow field around a spacecraft entering the Jovian atmosphere.     

The submillimeter-wave spectrum and spectroscopic constants of SO2 in the ground state

The submillimeter-wave spectrum of SO₂ has been recorded with 0.004 cm^?1 resolution in the region 8–90 cm^?1. About 2000 lines were observed, 1500 of which have been assigned to the ground state rotational transitions of ³²SO₂. Molecular constants up to the 10th order have been derived, combining our data with the available microwave data in the literature. SO₂ rotational spectrum line positions up to 90 cm^?1 can be reproduced from these constants, within the experimental accuracy (2 × 10^?4 cm^?1).