Accession Number:

ADA263457

Title:

Experimental and Theoretical Aspects of Excited State Electron Transfer and Related Phenomena: Conference Held in Honour of Zbigniew R. Grabowski in Pultusk, Poland on September 27-October 2, 1992

Descriptive Note:

Corporate Author:

POLISH ACADEMY OF SCIENCES WARSAW

Personal Author(s):

Report Date:

1992-10-01

Pagination or Media Count:

121.0

Abstract:

Reaction centers of Rhodopseudomonas Viridis were studied at ambient pressure 0.1 MPa and at three higher pressures, 120, 240, and 350 MPa using picosecond difference absorption spectroscopy. High pressure increased the rate of electron transfer from PHL-QA to PHLQA-, measured by the decay of the transient optical absorption of HL- in the 650 - 700 nm wavelength range, from 181 or - 17 ps-1 at 0.1 MPa to 127 or - 16 ps-1 at 120 MPa. At 240 MPa the decay became biexponential with a fast 198 or - 66ps-1 component of 33 amplitude and a slow component 7.8 or - 1.4 ns-1 of 67 amplitude. At 350 MPa the fast component was undetectable and only a slow exponential decay at 4. 1 or - 0.3 ns-1 was observed. The values for the fast component were also confirmed by measurement of the recovery of the absorption of HL in the 545 - 550 nm region and for the slow components by studying the recovery of the absorption of P in the 851 - 865 nm region. The slow component is attributed to the charge recombination process PHL-QA right arrow PHLQA.

Subject Categories:

  • Organic Chemistry
  • Physical Chemistry
  • Electricity and Magnetism
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE