Puzzarini Cristina
Dipartimento di Chimica G. Ciamician, Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy.
J Chem Phys. 2005 Jul 8;123(2):24313. doi: 10.1063/1.1953367.
The isomer pair HCSHSC and related cations have been studied by means of a highly accurate level of theory. For all the species investigated the near-equilibrium potential energy surface has been calculated using the coupled cluster method in conjunction with correlation consistent basis sets ranging in size from quadruple to sextuple zeta. After extrapolation to the complete basis set limit, additional corrections due to core-valence correlation and scalar relativistic effects have also been included. Consequently, the molecular and spectroscopic properties as well as the ionization potentials and dissociation energies have been predicted to high accuracy. Isomerization path and energy for both radical and cationic species have also been investigated. Finally, the anharmonic vibrational frequencies have been employed in order to obtain zero-point corrections to ionization potentials, dissociation energies, and isomerization barriers: IP0(HCS) = 7.57(4) eV and IP0(HSC) = 9.00(5) eV; D0(C-H) = 49.29(55) kcal/mol and D0(S-H) = 9.99(37) kcal/mol; deltaE0(HCSHSC) = 39.29(49) kcal/mol, and deltaE0(HCS+HSC+) = 72.24(75) kcal/mol.
通过高精度的理论水平对异构体对HCSHSC及相关阳离子进行了研究。对于所有研究的物种，使用耦合簇方法结合从四重到六重zeta大小不等的相关一致基组计算了近平衡势能面。在外推到完全基组极限后，还包括了由于芯价相关和标量相对论效应引起的额外校正。因此，分子和光谱性质以及电离势和解离能都得到了高精度的预测。还研究了自由基和阳离子物种的异构化路径和能量。最后，使用非谐振动频率来获得对电离势、解离能和异构化势垒的零点校正：IP0(HCS)=7.57(4)eV，IP0(HSC)=9.00(5)eV；D0(C-H)=49.29(55)kcal/mol，D0(S-H)=9.99(37)kcal/mol；ΔE0(HCSHSC)=39.29(49)kcal/mol，ΔE0(HCS+HSC+)=72.24(75)kcal/mol。
