Structural studies of photoinduced intramolecular electron transfer in cyclopentadienylnickelnitrosyl [electronic resource].

Published:: Washington, D.C. : United States. Dept. of Energy, 1994.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
Physical Description:: 52 pages : digital, PDF file
Additional Creators:: Argonne National Laboratory, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information

Access Online

www.osti.gov

Availability

Finding items...

Restrictions on Access:

Free-to-read Unrestricted online access

Summary:

A structural study based on EXAFS, FTIR, and optical absorption spectroscopies has been conducted on a photogenerated, metastable state of cyclopentadienylnickelnitrosyl (CpNiNO) produced by a reversible photochemical reaction. The photogenerated, metastable state with distinctively different EXAFS, IR, and optical absorption spectra from those of the ground state molecules was created by irradiating the sample with the 365 nm line of a mercury lamp at 20K . At the same temperature, the reverse reaction was induced by irradiation with the 313 nm line from the mercury lamp. Based on the analysis of the EXAFS data, the photogenerated, metastable state of CpNiNO has undergone considerable nuclear rearrangements compared to its ground state. The nuclear movement is characterized by a 0.12Å elongation of Ni-N bond and by a bending of Ni-N-O. A shift of the N-O stretching frequency from 1824 to 1387 cm{sup −1} was observed in the photoinduced reaction with 365 nm light, implying that a NO{sup −} like species results from intramolecular electron transfer from Ni to NO. The changes in the absorption spectra for the same reaction showed reduced absorption of the 385 nm band and a newly generated broad band near IR region. Temperature dependence of the Debye-Waller factor of CpNiNO was in good agreement with the diatomic harmonic oscillator for the Ni-N bond, but deviated for the Ni-O and the Ni-C bonds. Based on the structures obtained from EXAFS, ZINDO calculations for both the ground state and the photogenerated, metastable state of CpNiNO reproduced the general features of the observed absorption spectra and qualitatively explained the wavelength dependence of the reaction. The calculated partial charges on each atom in the ground state and the photogenerated, metastable state of CpNiNO are consistent with intramolecular electron transfer upon photoexcitation by 365 nm light.

Report Numbers:

E 1.99:anl/chm/pp--80920
anl/chm/pp--80920

Subject(s):

Other Subject(s):

Note:

Published through SciTech Connect.
03/01/1994.
"anl/chm/pp--80920"
"DE94008467"
Montano, P.A.; Bowman, M.K.; Norris, J.R.; Chen, L.X.; Wang, Zhiyu.

Funding Information:

W-31109-ENG-38

View MARC record | catkey: 14455905