Dipartimento di Chimica, Università di Torino, and NIS-Nanostructured Interfaces and Surfaces-Centre of Excellence, Via P. Giuria 7, 10125 Torino, Italy.
J Chem Phys. 2012 Jul 7;137(1):014103. doi: 10.1063/1.4731266.
The vibrational contribution to static and dynamic (hyper)polarizability tensors of polyacetylene are theoretically investigated. Calculations were carried out by the finite field nuclear relaxation (FF-NR) method for periodic systems, newly implemented in the CRYSTAL code, using the coupled perturbed Hartree-Fock scheme for the required electronic properties. The effect of the basis set is also explored, being particularly important for the non-periodic direction perpendicular to the polymer plane. Components requiring a finite (static) field in the longitudinal direction for evaluation by the FF-NR method were not evaluated. The extension to that case is currently being pursued. Whereas the effect on polarizabilities is relatively small, in most cases the vibrational hyperpolarizability tensor component is comparable to, or larger than the corresponding static electronic contribution.
本文从理论上研究了聚乙炔的振动对静态和动态（超）极化率张量的贡献。通过 CRYSTAL 代码中最新实现的有限场核弛豫（FF-NR）方法，利用耦合微扰哈特ree-fock 方案计算了周期性系统所需的电子性质。还探讨了基组的影响，对于垂直于聚合物平面的非周期性方向尤其重要。需要在纵向施加有限（静态）场才能通过 FF-NR 方法进行评估的分量未进行评估。目前正在对此情况进行扩展。虽然对极化率的影响相对较小，但在大多数情况下，振动超极化率张量分量与相应的静态电子贡献相当，或者更大。
