Balabin showed, from focal-point analysis and ab initio limit computations up to CCSD(T)/CBS, that this keto form is 31.4 ± 1.8 kJ mol -1 more stable than the enol form, in this case, 2amino-ethenol. The difference found here is |(-115.2) -(-77.3)| = 37.9 kJ mol -1 but this is for the most stable conformer of amino-acetaldehyde whose OCCN dihedral of 0