We investigate the stability and dissociation of methane, which is the most abundant organic molecule in the universe, using diamond anvil cell (DAC) with in situ Raman spectroscopy up to 903K and 21 GPa. At the tem...We investigate the stability and dissociation of methane, which is the most abundant organic molecule in the universe, using diamond anvil cell (DAC) with in situ Raman spectroscopy up to 903K and 21 GPa. At the temperatures of 793 and 723 K and the corresponding pressures of 16.15 and 20.30 GPa, methane dissociates to form carbon 'soot' and heavier hydrocarbons involving C=C and C≡C bonds. However, if the pressure is not very high, methane remains stability up to the highest temperature of 903 K of the work. The four symmetric C-H bonds of methane split at high temperatures and at high pressures, and there is at least one phase transition of crystalline symmetry from face centred cubic (fcc) to hexagonal close packed (hcp) before dissociation.展开更多
基金supported by the National Natural Science Foundation of China (20805030)Academic Leader Program of Shanghai Science and Technology Committee,China (07XD14014)+4 种基金Key Subject of Shanghai Municipal Education Commission,China (J50102)Key Project of the Ministry of Education of China(208182)National High Technology Research and Development Program of China (863) (2007AA03Z335)Science Foundation for the Excellent Youth Scholars of University (Shanghai),ChinaInnovative Foundation of Shanghai University,China~~
基金Supported by National Natural Science Foundation of China under Grant No. 20777048, and the Shanghai Leading Academic Disciplines (T105).
文摘We investigate the stability and dissociation of methane, which is the most abundant organic molecule in the universe, using diamond anvil cell (DAC) with in situ Raman spectroscopy up to 903K and 21 GPa. At the temperatures of 793 and 723 K and the corresponding pressures of 16.15 and 20.30 GPa, methane dissociates to form carbon 'soot' and heavier hydrocarbons involving C=C and C≡C bonds. However, if the pressure is not very high, methane remains stability up to the highest temperature of 903 K of the work. The four symmetric C-H bonds of methane split at high temperatures and at high pressures, and there is at least one phase transition of crystalline symmetry from face centred cubic (fcc) to hexagonal close packed (hcp) before dissociation.