Dynamics of a Chlorophyll Dimer in Collective and Local Thermal Environments

Journal Article · 30 January 2016 · Journal of Mathematical Chemistry

DOI: https://doi.org/10.1007/s10910-016-0593-z · OSTI ID:1338732

Merkli, M. ^[1]; Berman, Gennady Petrovich ^[2]; Sayre, Richard Thomas ^[3]; Gnanakaran, Sandrasegaram ^[2]; Konenberg, M. ^[4]; Nesterov, A.I. ^[5]; Song, H. ^[6]

---

1. Memorial Univ. of Newfoundland, St. John’s, NL (Canada). Dept. of Mathematics and Statistics
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division
3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Biological Division
4. Memorial Univ. of Newfoundland, St. Johnas, NL (Canada). Dept. of Mathematics and Statistics; Univ. Stuttgart, Stuttgart (Germany). Fachbereich Mathematik
5. CUCEI: Universidad de Guadalajara
6. Tianjin University of Technology

Here we present a theoretical analysis of exciton transfer and decoherence effects in a photosynthetic dimer interacting with collective (correlated) and local (uncorrelated) protein-solvent environments. Our approach is based on the framework of the spin-boson model. We derive explicitly the thermal relaxation and decoherence rates of the exciton transfer process, valid for arbitrary temperatures and for arbitrary (in particular, large) interaction constants between the dimer and the environments. We establish a generalization of the Marcus formula, giving reaction rates for dimer levels possibly individually and asymmetrically coupled to environments. We identify rigorously parameter regimes for the validity of the generalized Marcus formula. The existence of long living quantum coherences at ambient temperatures emerges naturally from our approach.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE Laboratory Directed Research and Development (LDRD) Program
• Grant/Contract Number: AC52-06NA25396; 15349
• OSTI ID: 1338732
• Report Number(s): LA-UR-15-29509
• Journal Information: Journal of Mathematical Chemistry, Vol. 54, Issue 4; ISSN 0259-9791
• Country of Publication: United States
• Language: English