2D surfaces of potential energy, dipole moment, and kinetic coefficients associated with internal rotation of the thiol groups in the HSOSH molecule were calculated and analyzed at MP2/CBS level of theory. Two stable conformers (trans- and cis-) with very close energies were found. Torsional vibrations of the HSOSH, DSOSH, and DSOSD molecules were calculated at harmonic and anharmonic approximations as well as by numerically solving of the 2D torsional Schrödinger equation using the Fourier method for the first time. The tunneling splitting of the first thirty torsional energy levels was found. The torsional IR spectra of the trans- and cis- conformers of the three analyzed molecules were calculated at different temperatures.

在MP2 / CBS的理论水平上计算和分析了HSOSH分子中与硫醇基团的内部旋转相关的势能，偶极矩和动力学系数的二维表面。发现了两个能量非常接近的稳定构象异构体（反式和顺式）。HSOSH，DSOSH和DSOSD分子的扭转振动是按谐波和非谐近似计算的，以及首次使用傅里叶方法对二维扭转Schrödinger方程进行数值求解。发现前三十个扭转能级的隧穿分裂。在不同温度下计算了三个被分析分子的反式和顺式构象的扭转红外光谱。