The conformational landscape of α-aminoglycine

International audienceThe conformational landscape of α-aminoglycine has been studied. A conformational search has been first done using a set of different low-cost computational methods. The conformers obtained have been finally optimized at MP2 and B3LYP-D3/6-311++G(2d,p) levels of theory. A conformational landscape of 15 conformers with relative energies lower than 2000 cm − 1 has been obtained. For the global minimum (IIa) a cooperative network formed by an O-H⋅⋅⋅N-H, NH⋅⋅⋅N and N-H⋅⋅⋅O-C hydrogen bonds, closing a sequential cycle stabilizes the structure. The next conformer in energy (Ia) also has two N-H⋅⋅⋅O-C, and N-H⋅⋅N and N-H⋅⋅⋅O-H hydrogen bonds. The potential energy surfaces associated with different torsions have been investigated, to rationalize the stability of some conformers. The relative population ratio in a supersonic jet has been estimated to calculate the relative intensity of the rotational spectra of the predicted conformers