Experimental Charge Density and Electrostatic Potential of Triglycine

Abstract

The experimental electron density distribution in triglycine has been determined using single-crystal X-ray diffraction data at 123 K to a resolution of (sin θ/λ)max = 1.1 Å−1. Several multipolar pseudo-atom density refinements were performed against the 7238 observed data in order to estimate the net charges on the atoms. The electrostatic potential around the two molecules is calculated from the parameters derived from these refinements. A charge transfer between the two triglycine molecules of the asymmetric unit is discussed. Crystal data: C6H11N3O4, Mr = 189.2, triclinic, P1¯, Z = 4 (two molecules in the asymmetric unit), T = 123 K, a = 11.585 (1), b = 14.603 (2), c = 4.800 (4) Å, α = 89.28 (3), β = 95.55 (2), γ = 104.484 (8)°, V = 782.5 (7) Å3, Dx = 1.61 g cm−3, μ = 1.5 cm−1 for λMo = 0.7107 Å.