Mossbauer Spectroscopy of Nitrogenase Components

蒙克博士正在继续他最先进的穆斯堡尔和EPR研究铁硫蛋白。他也在为价离域系统开发一个自旋耦合哈密顿量。在上一个赠款期间进行的工作使人们认识到，价离域系统中的自旋耦合需要一种称为双交换的额外机制。在试图用微观理论支持新的自旋哈密顿量时，蒙克博士发现了一种交换耦合（交换转移）机制。他计划现在尽可能详细地描述铁的各种状态。穆斯堡尔光谱和EPR光谱相互结合使用，可以很好地阐明铁硫团簇的活性位点性质。各种铁硫蛋白正在被研究，包括氮酶，一种能够将大气中的氮还原为氨的酶系统

Dr. Munck is continuing his state of the art Mossbauer and EPR studies on iron-sulfur proteins. He is also developing a spin-coupling Hamiltonian for valence-delocalized systems. Work performed in the previous grant period has lead to the recognition that spin-coupling in valence-delocalized systems requires an additional mechanism, called double-exchange. in attempting to buttress the new spin Hamiltonian by microscopic theory, Dr. Munck discovered a mechanism of exchange coupling (exchange-transfer). He plans to now describe the various states of iron in as much detail as possible. Mossbauer and EPR spectroscopy, used in conjunction, with each other are well suited to elucidate the active site properties of iron-sulfur clusters. A variety of iron-sulfur proteins are being studied, including nitrogenase, an enzyme system capable of reducing atmospheric nitrogen to ammonia.***//