Selective excitation, relaxation and energy channeling in molecular systems: Progress report, June 1, 1984-February 1, 1987. [Circular dichroism of helical polypeptides]
Technical Report
·
OSTI ID:6594500
Progress is reported in two major areas. The first area concerns the role of the microenvironment of a molecule in determining the pathways and rates of energy relaxation in molecules. We have derived a reduced equation of motion for the state of a molecule (or molecular system) containing memory effects due to interactions with its molecular environment. This equation lends itself to two important limits: linear-dissipative and nonlinear-coherent. We have already shown how the linear-dissipative limit leads to a generalized master equation. We have applied this equation to the calculation of coherence and other relaxation effects in simple two-level systems. We are currently studying the nonlinear-coherent limit for the case of excitation (exciton) transfer in helical polymers. The second area concerns the role of molecular interactions in determining the electronic spectral properties of helical biopolymers. We have demonstrated that the circular dichroism (CD) spectra of short helices have the same kind of component resolution into band types as do infinitely long polymers. Each of these component bands is related to the geometry of the helix, and they can be quantitatively extracted. Furthermore, we have shown that one of the principal component bands (the helix band) is greatly skewed by interactions - a feature not previously recognized. These are important results because they change the way experimental CD spectra of biopolymers should be interpreted and affect the analysis of previously published results. In addition, we have developed and applied theoretical-computational methods for the effects of solvent and secondary structure interations on CD spectra of biopolymers.
- Research Organization:
- Florida State Univ., Tallahassee (USA). Inst. of Molecular Biophysics
- DOE Contract Number:
- FG05-86ER60473
- OSTI ID:
- 6594500
- Report Number(s):
- DOE/ER/60473-1; ON: DE87005345
- Country of Publication:
- United States
- Language:
- English
Similar Records
cap alpha. -helical polypeptide circular dichroism component band analysis
Selective excitation, relaxation, and energy channeling in molecular systems. Comprehensive progress report, April 1990--July 1993
Selective excitation, relaxation, and energy channeling in molecular systems
Journal Article
·
Thu Jun 05 00:00:00 EDT 1986
· J. Phys. Chem.; (United States)
·
OSTI ID:5697371
Selective excitation, relaxation, and energy channeling in molecular systems. Comprehensive progress report, April 1990--July 1993
Technical Report
·
Sun Aug 01 00:00:00 EDT 1993
·
OSTI ID:10172435
Selective excitation, relaxation, and energy channeling in molecular systems
Technical Report
·
Sun Aug 01 00:00:00 EDT 1993
·
OSTI ID:6083400