摘要
激活低压金刚石气相生长过程是热力学耦合反应，在生长温度１２００Ｋ，压强为１０４ｋＰａ和激活温度为２４００Ｋ时，以石墨为原料最终生成金刚石是一个负熵（产生）反应（ΔｉＳ１＝－５．８０ＪＫ－１）；它在超平衡原子氢生成氢分子的正熵反应（ΔｉＳ２＝９３．９３ＪＫ－１）的推动下得以进行；耦合参数的经验值χ＝０．２８，生成低压金刚石的总反应熵产生（ΔｉＳ３＝ΔｉＳ１＋χΔｉＳ２＝２０．５０ＪＫ－１）是正值；符合热力学基本定律．负熵反应和热力学耦合术语被广泛用于解释生命现象，但以往从未找到定量的证明．
Activated low pressure diamond growth from the vapor phase is a thermodynamic coupling reaction. When T substrate =1 200 K,p=10 4 kPa and T activation =2 400 K,the transformation from graphite to diamond is a negative (entropy) reaction (Δ iS 1=-5.80 J·K -1 ); it is driven by the positive entropy production reaction of hydrogen molecule from superequilibrium atomic hydrogen (Δ iS=93.93 J·K -1 ); with the empirical value of coupling parameter χ=0.28,the total entropy production (Δ iS 3=Δ iS 1+Δ iS 2=20.50 J·K -1 ) is positive which means that the total coupling reaction for diamond synthesis is thermodynamically reasonable even under low pressure. The terms of negative entropy reaction and coupling reaction are widely used for explaining “what is life”,but none of them could be quantitatively confirmed before.
出处
《复旦学报（自然科学版）》
CAS
CSCD
北大核心
1999年第1期75-79,83,共6页
Journal of Fudan University：Natural Science
基金
国家自然科学基金
高技术新材料基金
国家教育部科技司资助课题
关键词
负熵反应
热力学耦合
人造金刚石
低压
气相生长
negative entropy reaction
thermodynamic coupling
diamond
noneqilibrium thermodynamics
