Near-perfect Dipole Parallel-alignment in the Highly Anisotropic Crystal Structure of 4-iodoacetophenone-(4-methoxyphenylethylidene) Hydrazone

The title compound crystallizes in the space group Pna 2(1) with cell parameters a = 6.4606(3), b = 7.2155(3) and c = 33.5878(16) Å. The azine shows a gauche conformation about the N-N bond and there is an angle of 58.1° between the benzene rings of each azine. This conformation allows for two intermolecular arene-arene T-contacts between pairs of benzene rings. The characteristic structural motif features T-contact formation between like-substituted arene rings and this architecture results in a highly dipole-parallel aligned lattice. All azines are perfectly colinear within each layer and the orientations of the azines in different layers are nearly the same. The surfaces of the layers exhibit a quadrilateral kite-shaped arrangement of I-atoms and of OCH ₃ -substituents. The layers pack such that the OCH ₃ -carbon atoms are placed above the interstices between the I-atoms in the adjacent layer.