通过转动光谱学和从头算计算相结合的方法对硝酰氯的分子几何结构和电子结构进行的研究。

An investigation of the molecular geometry and electronic structure of nitryl chloride by a combination of rotational spectroscopy and ab initio calculations.

作者信息

Francis S G, Harvey J N, Walker N R, Legon A C

机构信息

School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom.

出版信息

J Chem Phys. 2008 May 28;128(20):204305. doi: 10.1063/1.2920487.

DOI:10.1063/1.2920487

PMID:18513017

Abstract

The ground-state rotational spectra of the six isotopomers (16)O(2) (14)N(35)Cl, (16)O(2) (14)N(37)Cl, (18)O(16)O(14)N(35)Cl, (18)O(2) (14)N(35)Cl, (16)O(2) (15)N(35)Cl, and (16)O(2) (15)N(37)Cl of nitryl chloride were observed with a pulsed-jet, Fourier-transform microwave spectrometer to give rotational constants, Cl and (14)N nuclear quadrupole coupling, and spin-rotation coupling constants. These spectroscopic constants were interpreted to give r(0), r(s), and r(m) ((2)) versions of the molecular geometry and information about the electronic redistribution at N when nitryl chloride is formed from NO(2) and a Cl atom. The r(m) ((2)) geometry has r(N-Cl)=1.8405(6) A, r(N-O)=1.1929(2) A, and the angle ONO=131.42(4) degrees , while the corresponding quantities for the r(s) geometry are 1.8489 A, 1.1940 A, and 131.73 degrees , respectively. Electronic structure calculations at CCSD(T)cc-pVXZ (X=T, Q, or 5) levels of theory were carried out to give a r(e) geometry, vibration-rotation corrections to equilibrium rotational constants, and values of the (35)Cl and (14)N nuclear hyperfine (quadrupole and spin-rotation) coupling constants in good agreement with experiment. The equilibrium geometry at the CCSD(T)/cc-pV5Z level of theory has r(N-Cl)=1.8441 A, r(N-O)=1.1925 A and the angle ONO=131.80 degrees . The observed rotational constants were corrected for the vibration-rotation effects calculated ab initio to yield semiempirical equilibrium constants which were then fitted to give the following semiempirical equilibrium geometry: r(N-Cl)=1.8467(2) A, r(N-O)=1.1916(1) A, and the angle ONO=131.78(3) degrees .

摘要

利用脉冲喷射傅里叶变换微波光谱仪观测了硝酰氯的六种同位素异构体（(^{16}O_2\ ^{14}N^{35}Cl)、(^{16}O_2\ ^{14}N^{37}Cl)、(^{18}O^{16}O\ ^{14}N^{35}Cl)、(^{18}O_2\ ^{14}N^{35}Cl)、(^{16}O_2\ ^{15}N^{35}Cl)和(^{16}O_2\ ^{15}N^{37}Cl)）的基态转动光谱，以得到转动常数、氯和氮的核四极耦合以及自旋 - 转动耦合常数。对这些光谱常数进行解释，以给出分子几何结构的(r(0))、(r(s))和(r(m))（(2)）版本，以及当由(NO_2)和一个氯原子形成硝酰氯时氮原子处电子重新分布的信息。(r(m))（(2)）几何结构中(r(N - Cl)=1.8405(6)\mathring{A})，(r(N - O)=1.1929(2)\mathring{A})，(\angle ONO = 131.42(4)^{\circ})，而(r(s))几何结构的相应量分别为(1.8489\mathring{A})、(1.1940\mathring{A})和(131.73^{\circ})。在CCSD(T)/cc - pVXZ（(X = T)、(Q)或(5)）理论水平上进行了电子结构计算，以给出(r(e))几何结构、对平衡转动常数的振动 - 转动校正以及(^{35}Cl)和(^{14}N)核超精细（四极和自旋 - 转动）耦合常数的值，这些值与实验结果吻合良好。在CCSD(T)/cc - pV5Z理论水平上的平衡几何结构为(r(N - Cl)=1.8441\mathring{A})，(r(N - O)=1.1925\mathring{A})，(\angle ONO = 131.80^{\circ})。对观测到的转动常数进行了从头算计算得到的振动 - 转动效应校正，以得到半经验平衡常数，然后对其进行拟合，得到如下半经验平衡几何结构：(r(N - Cl)=1.8467(2)\mathring{A})，(r(N - O)=1.1916(1)\mathring{A})，(\angle ONO = 131.78(3)^{\circ})。