title: Magnetic properties of oxyhemoglobin.
abstract: When the magnetic susceptibility of frozen aqueous solutions of human oxyhemoglobin was measured in the range between 25 and 250 K, it showed a temperature-dependent behavior typical of a thermal equilibrium between a ground singlet state and an excited triplet state for two electrons per heme, the energy separation being [2J] = 146 cm-1. By contrast, within the same temperature range, carboxyhemoglobin was found to be diamagnetic, as already reported.
mesh_terms: D002263:Carboxyhemoglobin; D006801:Humans; D008280:Magnetics; D010108:Oxyhemoglobins; D011487:Protein Conformation; D013696:Temperature; D013816:Thermodynamics
chemical_list: D010108:Oxyhemoglobins; D002263:Carboxyhemoglobin
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