First hyperpolarizability of some nonconjugated donor–acceptor 3D molecules: noncentrosymmetric crystal through conformational flexibility
作者:K. Srinivas、Sanyasi Sitha、V. Jayathirtha Rao、K. Bhanuprakash、K. Ravikumar、S. Philip Anthony、T. P. Radhakrishnan
DOI:10.1039/b414311f
日期:——
Four derivatives of 2,4,6-tris(benzylamino)-1,3,5-triazine are synthesized and detailed computational and nonlinear optical investigations are carried out. Computations indicate near degenerate conformations (C3 and C1 symmetry) in all systems in the gas phase; the dipole moments are also of similar magnitude in all of them except molecule 4
[2,4,6-tris(4-fluorobenzylamino)-1,3,5-triazine]. HRS measurements of these molecules in solution reveal moderately large β values; structureâproperty relations are analyzed through computations. These molecules have one added advantage of nearly 100% optical transmission through the visible range, due to the nonconjugated structure. Molecule 4 crystallizes in a noncentrosymmetric structure by adopting the conformation with the lower dipole moment; it also shows optical SHG in the solid state.
我们合成了四种 2,4,6-三(苄基氨基)-1,3,5-三嗪的衍生物,并进行了详细的计算和非线性光学研究。计算结果表明,在气相中,所有体系的构象都接近于退化构象(C3 和 C1 对称性);除了分子 4 [2,4,6-三(4-氟苄基氨基)-1,3,5-三嗪]之外,所有分子的偶极矩大小也相似。对这些分子在溶液中的 HRS 测量显示了中等大的δ值;通过计算分析了结构与性质的关系。这些分子的另一个优点是,由于其非共轭结构,在可见光范围内几乎具有 100% 的透光率。分子 4 采用偶极矩较低的构象,以非中心对称结构结晶;它在固态下也显示出光学 SHG。