XAFS and crystallographic studies of Ni(II) porphyrins in single crystals and in solution
Abstract. Nickel porphyrins serve as models for the active sites of several biological processes. Crystallographic and EXAFS results for a Ni meso-tetrapropyl porphyrin (NiTPrP) yield different Ni-N distances in solution and in the solid state. The Ni-N distances determined by single crystal polarized XAS and X-ray diffraction agree well. Polarized XANES experiments further establish that the pre-edge feature observed in square planar Ni(II) complexes is a ls-4pz transition. The single crystal and solution EXAFS results demonstrate that conformational variations of the porphyrin macrocycle can readily be imposed by environmental and/or packing forces and can thereby modulate the chemical and physical properties of porphyrinic chromophores and prosthetic groups.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC02-76CH00016
- OSTI ID:
- 383557
- Report Number(s):
- BNL-63345; CONF-9608104-2; ON: DE96014535
- Resource Relation:
- Conference: 9. international conference on x-ray absorption fine structure (XAFS), Genoble (France), 26-30 Aug 1996; Other Information: PBD: [1996]
- Country of Publication:
- United States
- Language:
- English
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