Experimental and theoretical investigations of a sulfur-33 electric-field-gradient (EFG) tensor of disulfide bonds in ³³S-labled dibenzyl disulfide have been presented. Temperature dependence of quadrupolar frequencies, ν_Q, is observed in the temperature range between 80 and 280 K, in which single peaks appear in all the ³³S nuclear quadrupole resonance (NQR) spectra. Analysis of nutation echo ³³S NQR spectra at 200 K yields the quadrupolar coupling constant, C_Q value, of 46.8(6) MHz and the asymmetry parameter, η_Q, of 0.48(7). The orientation of the ³³S EFG tensor of the disulfide is obtained by quantum chemical calculations: the largest EFG tensor component, V_ZZ, is approximately perpendicular to the molecular plane (C-S-S), and the smallest component, V_XX, is approximately 41° off the C-S bond. Extensive quantum chemical calculations are systematically performed to investigate dependences of ³³S EFG tensors on changes of torsion angles in disulfide and trisulfide bonds, indicating that analysis of ν_Q and C_Q values potentially makes it possible to assign the secondary structures of cross-linking in a rubber.

进行了实验和理论研究的³³ S标记的二苄基二硫的二硫键的硫33电场梯度（EFG）张量。四极频率的温度依赖性，ν _Q，在温度范围80至280之间K，其中单峰出现在所有观察到的³³核极共振（NQR）光谱。章动的分析回声³³在200 K之后将产生四极耦合常数，S NQR谱Ç _Q值，46.8（6）MHz和不对称参数，η _Q，为0.48（7）。³³的方向二硫化物的EFG张量通过量子化学计算获得：最大的EFG张量分量V _ZZ近似垂直于分子平面（CSS），最小的分量V _XX偏离CS键约41°。广泛量子化学计算被系统地进行调查的依赖性³³上在二硫化物和三硫化物键扭转角的变化小号EFG张量，表明ν的该分析_Q和C ^ _Q值可能使得能够分配在交联的二级结构橡胶。