ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
A variational procedure has been applied in conjunction with the linear combination of atomic orbitals (molecular orbitals) [LCAO(MO)] method for electronic structure investigations to study the unquenching of the orbital angular momentum due to the influence of spin–orbit interaction in large biomolecular systems and its influence on the magnetic hyperfine fields, especially at 57mFe nuclei. Application is made to azidomyoglobin and it is found that incorporation of spin–orbit effects leads to drastic effects on the hyperfine fields as suggested from earlier investigations based on the crystal field model. In contrast to the values of 37, 166, and 13 kG obtained without incorporation of orbital unquenching effects and with the external magnetic field applied along the a, b, and c axes of the crystal, the values we obtained when orbital unquenching effects are included are 252, 133, and 116 kG which agree considerably better with the experimental values of 185±5, 133±5, and 99±5 kG from Mössbauer measurements. Suggestions are made for bridging the remaining gap between theory and experiment.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.456205
