The crystal and molecular structure of maleic acid

Abstract

Maleic acid (cis ethylene dicarboxylic acid (CH. COOH)2) crystals were prepared from acetone in a new habit, platy on (001). The structure is monoclinic, a-7.47, b=10-15, c-7.65 A, fl=123.5 °, Q-1.599 g.cm.-a; P21/c, 4 asymmetric molecules per unit cell. A systematic analysis by trial and error gave a preliminary structure, which was refined by three Fourier projections and then by a three-dimensional Fourier section through the molecular plane and by eight line syntheses through the centres of the atoms, using 885 structure factors.