TY - DATA T1 - Raman Spectroscopic Investigations of Pressure-Induced Phase Transitions in n-Hexane PY - 2007/12/27 AU - G. Kavitha AU - Chandrabhas Narayana UR - https://acs.figshare.com/articles/journal_contribution/Raman_Spectroscopic_Investigations_of_Pressure_Induced_Phase_Transitions_in_i_n_i_Hexane/2966170 DO - 10.1021/jp075188o.s001 L4 - https://ndownloader.figshare.com/files/4665325 KW - 9.1 GPa KW - Raman Spectroscopic Investigations KW - transition KW - methyl end group N2 - We report high-pressure Raman studies on n-hexane up to 16 GPa. n-Hexane undergoes solid−solid transition around 9.1 GPa along with an already reported liquid−solid transition around 1.4 GPa. The intensity ratio of the Raman modes relating the all-trans conformation (1147 and 2872 cm-1) to that of the gauche conformation (1074 and 2923 cm-1) shows a sudden change across 9.1 GPa, suggesting an increase in the all-trans population conformers above 9.1 GPa. The disappearance of the torsional modes suggests a steric hindrance to the methyl end group, similar to the n-heptane case, suggesting that the high-pressure phase (above 9.1 GPa) is an orientationally disordered phase. In general, the transition pressure for the solid−solid transition is inversely proportional to the length of the carbon backbone in the medium chain length n-alkanes. ER -