Fluctuations of Pigment’s Dipole Moment Orientations in B850 Ring from Photosynthetic Complex LH2

Properties of light–harvesting (LH) pigment–protein complexes are strongly influenced by interactions with environment. Some of these interactions could be modeled by different types of static disorder. Slow fluctuations of bacteriochlorophyll’s dipole moment orientations represent one possible type of static disorder in B850 ring from LH2 complex of purple bacteria. This type of static disorder is investigated in present paper. Two modifications of such uncorrelated static disorder type (Gaussian fluctuations of dipole moment orientations in the ring plane and Gaussian fluctuations of dipole moment orientations in a plane which is perpendicular to the ring one) are taking into account. The nearest neighbour transfer integral distributions for different strengths of static disorder are presented and the most important statistical properties are calculated, discussed and compared. Key–Words: LH2 complex, B850 ring, static disorder, Hamiltonian, transfer integral distributions