Abstract
Poly(L-leucine) is one of the polyamino acids having a bulky hydrophobic side-chain. For want of full phonon dispersion curves and density-of-states on this biopolymer Roleset al have interpreted their specific heat data in a limited way. In the present communication we report an analysis of the normal modes and their dispersion for poly(L-leucine) which leads to a very good agreement of the specific heat calculations with experimental measurements. It is observed that the main contribution to specific heat comes from the coupling of the back-bone skeletal and side-chain modes. Several other assignments have been revised. A special feature of some dispersion curves is their tendency to bunch in the neighbourhood of helix angle. It has been attributed to the presence of strong intramolecular interactions. Repulsion between the dispersion curves is also observed.
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References
B Wunderlich and H S Bu,Thermochimica Acta 119, 225 (1987)
H S Bu, W Aycock, Z D Cheng Stephen and B Wunderlich,Polymer 29, 1486 (1988)
K A Roles and B Wunderlich,Biopolymers 31, 477 (1991)
K A Roles, A Xenopoulos and B Wunderlich,Biopolymers 33, 753 (1993)
V D Gupta, S Trevino and H Boutin,J. Chem. Phys. 48, 3008 (1968)
M V Krishnan and V D Gupta,Chem. Phys. Lett. 6, 231 (1970)
M V Krishnan and V D Gupta,Chem. Phys. Lett. 7, 285 (1970)
R D Singh and V D Gupta,Spectrochim. Acta A27, 385 (1971)
A M Dwivedi and V D Gupta,Chem. Phys. Lett. 16, 909 (1972)
V D Gupta, R D Singh and A M Dwivedi,Biopolymers 12, 1377 (1973)
R B Srivastava and V D Gupta,Biopolymers 13, 1965 (1974)
L Burman, P Tandon, V D Gupta, S Rastogi, S Srivastava and G P Gupta,J. Phys. Soc. Jpn. 64, 327 (1995)
A Gupta, P Tandon, V D Gupta, S Rastogi and G P Gupta,J. Phys. Soc. Jpn. 64, 315 (1995)
L Burman, P Tandon, V D Gupta, S Rastogi and S Srivastava,Polymer. J. April (1995) (in press)
O Prasad, P Tandon, V D Gupta, and S Rastogi,J. Phys. Soc. Jpn. 64, (1995)
E R Blout, C de Loze, S M Bloom and G D Fasman,J. Am. Chem. Soc. 82, 3787 (1960)
J L Koenig and P L Sutton,Biopolymers 10, 89 (1971)
K Itoh, T Shimanouchi and M Oya,Biopolymers 7, 649 (1969)
E B Wilson, J C Decuis and P C Cross,Molecular vibrations: The theory of infrared and Raman vibrational spectra (Dover Publications, New York, 1980)
P W Higgs,Proc. R. Soc. (London) A220, 472 (1953)
W T King, I M Mills and B L Crawford,J. Chem. Phys. 27, 455 (1957)
T H Benzinger,Nature (London) 229, 100 (1971)
R Pan, M Verma-Nair and B Wunderlich,J. Therm. Anal. 35, 955 (1989)
S Krimm and J Bandekar,Adv. Protein Chem. 38, 181 (1986)
D I Bower and W F Maddams,The vibrational spectroscopy of polymers (Cambridge University Press, 1989) 154–156
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Srivastava, S., Tandon, P., Gupta, V.D. et al. Heat capacity and phonons in poly(L-leucine). Pramana - J Phys 45, 235–254 (1995). https://doi.org/10.1007/BF02848416
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DOI: https://doi.org/10.1007/BF02848416