Montgomery W, Zaug J M, Howard W M, Goncharov A F, Crowhurst J C, Jeanloz R
Department of Earth and Planetary Science, University of California, Berkeley, 307 McCone Hall, Berkeley, California 94720-4767, USA.
J Phys Chem B. 2005 Oct 20;109(41):19443-7. doi: 10.1021/jp051967y.
We have determined the melting temperature of formic acid (HCOOH) as a function of pressure to 8.5 GPa using infrared absorption spectroscopy, Raman spectroscopy and visual observation of samples in a resistively heated diamond-anvil cell. The experimentally determined incongruent melting curve compares favorably with a two-phase thermodynamic model. Decomposition reactions were observed above the melting temperature up to a pressure of 6.5 GPa, with principal products being CO2, H2O, and CO. At pressures above 6.5 GPa, decomposition led to reaction products that could be quenched as solids to zero pressure, and infrared and Raman spectra indicate that pressure leads to the presence of sp3 carbon-carbon bonding in these reaction products.
我们利用红外吸收光谱、拉曼光谱以及在电阻加热金刚石对顶砧细胞中对样品的目视观察，测定了甲酸（HCOOH）在高达8.5吉帕压力下的熔化温度与压力的函数关系。实验测定的不一致熔化曲线与两相热力学模型吻合良好。在熔化温度以上直至6.5吉帕的压力范围内观察到了分解反应，主要产物为二氧化碳、水和一氧化碳。在6.5吉帕以上的压力下，分解产生的反应产物可以作为固体淬冷至零压力，红外光谱和拉曼光谱表明，压力导致这些反应产物中存在sp3碳 - 碳键。
