Browsing by Author "Wickremarachchi, P.A.S.R."

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    FTIR studies of molecular disorder in long chain n-alkanes: Chain tilt and chain end disorder
    (Macromolecular Symposia, 2002) de Silva, D.S.M.; Gorce, J.P.; Wickremarachchi, P.A.S.R.; Spells, S.J.
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    Study of disorder in different phases of tetratriacontane and binary alkane mixture, using vibrational spectroscopy
    (Journal of Physical Chemistry, 2007) Wickremarachchi, P.A.S.R.; Spells, S.J.; de Silva, D.S.M.
    Raman spectroscopy has been used to investigate the monoclinic crystal f rotator f melt phase transitions in n-C34H70, for both real-time heating and cooling runs. Changes in band intensity and frequency in the CH2 bending, CH2 twisting, skeletal C-C stretching, and CH3 rocking regions revealed both transitions, particularly when using band components related to gauche bonds. In the room temperature infrared spectrum, the CH2 rocking-twisting and CH2 wagging progressions were observed and indexed for n-C34H70 and a 2:1 (w/w) mixture of C34H70 and C36D74. This led to best estimates for the all-trans crystal core in both cases of 33 to 34 carbon atoms, indicating that the core corresponds to almost the whole of the C34H70 molecule.