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H2NCH2CN+H2O→H2NCH2C(OH)NH是一个重要的反应,涉及到星际媒介中甘氨酸的形成,与早期地球上的氨基酸起源有关.如果没有考虑氢隧道效应,在MP2/6-311+G(d,p)级别上计算反应能垒是254.7kJ·mol-1,在星际媒介中该气相反应很难进行.在星际媒介冰颗粒表面上,水分子催化反应增强了该化学反应的活性.H2NCH2CN与(H2O)3反应中的两个水分子作为催化剂降低活化能77.5kJ·mol-1和活化自由能70.9kJ·mol-1,并且通过氢键桥协同传递质子.量子氢隧道对于该反应进行至关紧要,采用小弯曲隧道(SCT)近似和正则变分过渡态理论(CVT)方法研究.温度50K时,速率常数kSCT/CVT为1.86×10-23cm3·molecule-1·s-1,表明在星际媒介中通过质子隧道机理该反应容易进行.研究结果与地球上的氨基酸起源于地球本身物质的观点相一致.
H2NCH2CN + H2O → H2NCH2C (OH) NH is an important reaction involved in the formation of glycine in the interstellar media, which is related to the origin of amino acids in early earth. Without considering the hydrogen tunneling effect, , p) is 254.7 kJ · mol-1, which is very difficult to perform in the interstellar medium. The catalytic reaction of water molecules enhances the activity of this chemical reaction on the surface of interstellar ice particles.H2NCH2CN and (H2O) 3 as a catalyst to reduce the activation energy of 77.5kJ · mol-1 and the activation energy of 70.9kJ · mol-1, and the synergistic transfer of protons through the hydrogen bond bridge. Quantum hydrogen tunneling for the reaction to Closely related, the small-bend tunnel (SCT) approximation and the theory of regular variation transition state theory (CVT) were used to study the rate constants kSCT / CVT of 1.86 × 10-23cm3 · molecule-1 · s- The reaction is facilitated by a proton tunneling mechanism in the interstellar medium that is consistent with the view that the amino acids on Earth originate in the Earth’s own substance.