Crystal and molecular structure of monoglycine nitrate

Abstract

The crystal and molecular structure of monoglycine nitrate (C₂ H₆ NO⁺ ₂, NO⁻ ₃) has been determined by single-crystal X-ray diffraction methods. The crystals are orthorhombic: space groupP2₁2₁2₁,a = 16.42(6),b = 6.10(4),c = 5.61(5) Å andZ = 4. The structure has been solved by direct phase determination methods, using visually-estimated intensity data, and was refined to anR -value of 0.064, using counter-measured intensity data for 660 reflections. The anomalous scattering by oxygen and nitrogen atoms suggests the present configuration.

The molecule in the structure exists as⁺NH₃CH₂CO₂H, NO⁻ ₃. The glycinium molecule is planar, except for the N(amino) atom, which deviates by 0.48 Å from the molecular plane defined by the atoms C(1), C(2), O(1) and O(2). The torsion angle N(1), C(2), C(1), O(1) is 20.7 °. The NH₃ group is a donor of three hydrogen bonds of equal strength (N ... 0 = 2.85 Å). Two of the hydrogen atoms of the NH₃ group also form weak bifurcated hydrogen bonds (N ... 0 = 3.04 Å). One of the carboxyloxygen atoms is a donor of a hydrogen bond (0 ... 0 = 2.65 Å). The oxygen atom of the carboxyl group and the oxygen atoms of the nitrate group are all acceptors of hydrogen bonds.