Structural studies of a series of organic non-linear optical materials

被引：16

作者：

Cole, JC ^{[1
]}

Cole, JM ^{[1
]}

Cross, GH ^{[1
]}

Farsari, M ^{[1
]}

Howard, JAK ^{[1
]}

Szablewski, M ^{[1
]}

机构：

[1] UNIV DURHAM,DEPT PHYS,DURHAM DH1 3LE,ENGLAND

来源：

ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE | 1997年 / 53卷

关键词：

D O I：

10.1107/S010876819601525X

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The crystal structures of {(4-[bis(diethylamino)-methylium]phenyl}dicyanomethanide (I), {4-[cyano(4-methylpiperidyl)methylium]phenyl} dicyanomethanide (II), {4-[cyano(1-pyrrolidinyl)methylium]phenyl}dicyanomethanide (IV) and (Z)-{4-[1,3-dicyano-3-(diethylamino)-2-propenylium]phenyl}dicyanomethanide have been determined by X-ray crystallography. Together with (Z)-{4-[1-cyano-3-(diethylamino)-2-propenylium]phenyl}dicyanomethanide [(III): Cole, J. C., Howard, J. A. K., Cross, G. H. & Szablewski, M. (1995). Acta Cryst. C51, 715-718], these compounds exhibit varying degrees of quinoidal characteristics and yet have predominantly zwitterionic ground state character. The presence of high dipole moments in the crystal can thus be inferred and are substantiated by measurements of high solution-state dipole moments. Negative solvatochromism (hypsochromism on increasing solvent polarity) confirms the zwitterionic character in at least two of the series.

引用

页码：812 / 821

页数：10

共 25 条

[1] TABLES OF BOND LENGTHS DETERMINED BY X-RAY AND NEUTRON-DIFFRACTION .1. BOND LENGTHS IN ORGANIC-COMPOUNDS [J].