X-Ray crystal structure of the electro-optic material meta-nitroaniline

Abstract
The crystal and molecular structure of the title compound has been determined from three-dimensional X-ray data by Patterson methods. Crystals are orthorhombic, a= 6·501(2), b= 19·330(4), and c= 5·082(2)Å, space group Pbc21, and Z= 4. Full-matrix least-squares refinement, using 541 independent reflections, has reached R 0·084. The molecular structure is unexceptional, with mean C–C, C–N, and N–O distances of 1·384, 1·423, and 1·227 Å. The molecule is almost perfectly planar, but some of the exocyclic atoms may be fractionally distorted out of the plane of the benzene ring. The packing of the molecules is quite different from that recently suggested on the basis of packing considerations, and has been shown to correlate well with the linear electro-optic properties.