Determination of the zero-field splitting in human acid methemoglobin by millimeter and submillimeter ESR experiments

Abstract The zero-field splitting of the high spin ferric ion in a frozen solution of acid methemoglobin is determined from the frequency dependence of the g- value . The number of different wavelengths available in a wide range (4-0.7 mm) make it possible to obtain the result within an accuracy of 2%.