CEMDRX, Physics Department, University of Coimbra, P-3004-516 Coimbra, Portugal.
J Phys Chem A. 2010 Feb 25;114(7):2607-17. doi: 10.1021/jp909005q.
N,N',N''-triphenylguanidinium carboxylate salts have been prepared by acid-base reactions of triphenylguanidine with formic, benzoic, and m-methoxybenzoic acids, and their single-crystal X-ray structure analysis has been performed. The salts were found to crystallize into noncentrosymmetric structures with an orthorhombic space group P2(1)2(1)2(1) for the formate and m-methoxybenzoate salts and a monoclinic space group Cc for the benzoate salt. The anions and cations are linked by intermolecular hydrogen bonds with the same motifs in the three salts. By using the molecular structures, the molecular first hyperpolarizabilities of several clusters were determined by semiempirical methods, and the components of the second-order susceptibility tensor, d, of triphenylguanidine and those of the reported crystals were evaluated using the oriented gas model with two different local-field corrections. The efficiency of the second-harmonic generation of triphenylguanidine and that of the reported triphenylguanidinium salts were measured using the Kurtz and Perry powder method.
N,N',N''-三苯基胍的羧酸盐通过三苯基胍与甲酸、苯甲酸和间甲氧基苯甲酸的酸碱反应制备，并对其进行了单晶 X 射线结构分析。发现这些盐都结晶成非中心对称结构，其中甲酸盐和间甲氧基苯甲酸盐为正交空间群 P2(1)2(1)2(1)，而苯甲酸盐为单斜空间群 Cc。阴离子和阳离子通过分子间氢键连接，在三种盐中具有相同的模式。利用分子结构，通过半经验方法确定了几个团簇的分子第一超极化率，并使用具有两种不同局部场校正的取向气体模型评估了三苯基胍的二阶介电张量分量 d 以及报道晶体的相应分量。使用 Kurtz 和 Perry 粉末法测量了三苯基胍和报道的三苯基胍盐的倍频效率。
