STRUCTURES OF ETHYLAMMONIUM HYDROGEN SUCCINATE AND DIETHYLAMMONIUM HYDROGEN SUCCINATE AT 110-K

C2H5NH3+.C4H5O4-, M(r) = 163.17, triclinic, P1BAR, a = 8.293 (1), b = 9.342 (6), c = 10.934 (2) angstrom, alpha = 88.94 (3), beta = 89.39 (1), gamma = 84.46 (2)-degrees, V = 842.9 (8) angstrom 3, Z = 4, D(x) = 1.286 g cm-3, lambda(Mo K-alphaBAR) = 0.71073 angstrom, mu = 1.008 cm-1, F(000) = 352, T = 110 K, R = 0.052 for 1885 observed reflections. (C2H5)2NH2+.C4H5O4-, M(r) = 191.23, orthorhombic, Pban, a = 12.661 (2), b = 10.125 (1), c = 8.031 (1) angstrom, V = 1029.5 (5) angstrom 3, Z = 4, D(x) = 1.234 g cm-3, lambda(Mo K-alphaBAR) = 0.71073 angstrom, mu = 0.918 cm-1, F(000) = 416, T = 110 K, R = 0.040 for 2007 observed reflections. In both compounds the hydrogen succinate ions are linked by very short hydrogen bonds resulting in infinite chains. In ethylammonium hydrogen succinate the chains are formed by two distinct succinate entities which alternate in the structure. They are connected by two short hydrogen bonds, both asymmetric. One hydrogen bond with length 2.483 (4) angstrom is between a carboxylic acid group and a carboxylate group, while the other short hydrogen bond with length 2.456 (4) angstrom is between two half ionized, but not identical, COO groups. Diethylammonium hydrogen succinate contains a crystallographically symmetric short hydrogen bond with length 2.4370 (7) angstrom. The H atom in the short hydrogen bond seems to be best described by two equally populated sites on each side of the center of the bond. The chains of anions are interconnected by longer hydrogen bonds to the cations in both compounds.