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li5237001

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ice_rain(金币+1):xiexie~ 2010-03-24 21:56
广义的第一原理包括两大类,以Hartree-Fork自洽场计算为基础的ab initio从头算,和密度泛函理论(DFT)计算。ab initio专指从头算,而第一性原理和所谓量子化学计算特指密度泛函理论计算。
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11楼2010-03-24 14:38:37
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li5237001

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ice_rain(金币+1):xiexie! 2010-03-24 21:56
 从头算(ab initio)是狭义的第一性原理计算,它是指不使用经验参数,只用电子质量,光速,质子中子质量等少数实验数据去做量子计算。但是这个计算很慢,所以就加入一些经验参数,可以大大加快计算速度,当然也会不可避免的牺牲计算结果精度。
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12楼2010-03-24 14:39:23
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wxyuer

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ice_rain(金币+2):xiexie! 2010-03-24 21:57
引用回帖:
Originally posted by li5237001 at 2010-03-24 14:38:37:
广义的第一原理包括两大类,以Hartree-Fork自洽场计算为基础的ab initio从头算,和密度泛函理论(DFT)计算。ab initio专指从头算,而第一性原理和所谓量子化学计算特指密度泛函理论计算。

好像不是楼主说的这回事,现在ab initio 与 first principles 概念已经混用了,都有第一性,从头计算的意思。随手就可找几个最新文献(这里 ab initio 就是采用的DFT理论,而不是楼主所说的那样,一般而言,做化学喜欢用ab initio,做物理的喜欢用first principles,早期大家喜欢用ab initio,现在大家一般喜欢用 first principles)
Ab initio lattice dynamics and thermodynamics of RuO2(110) surfaces,来源出版物: PHYSICAL REVIEW B    卷: 81    期: 8  文献编号: 081405    出版年: FEB 2010   
摘要: Using ab initio density-functional perturbation theory the lattice dynamics of the RuO2(110) O-bridge terminated surface has been extensively studied. Excellent agreement with high-resolution electron-energy-loss spectroscopy measurements was obtained. It was found that the (1 x 1) surface is unstable over a wide range of reciprocal-lattice vectors. This suggests that substrate and/or defect influence play a more important role for the stability of the (1 x 1) structure than thought so far, with important consequences for catalysis. ......

Electron-lattice instabilities suppress cuprate-like electronic structures in SrFeO3/OSrTiO3 superlattices,来源出版物: PHYSICAL REVIEW B    卷: 81    期: 8  文献编号: 085109    出版年: FEB 2010 ,
摘要: Using ab initio density-functional theory we explore the behavior of thin layers of metallic d(4) SrFeO3 confined between the d(0) dielectric SrTiO3 in a superlattice geometry. We find that the presence of insulating SrTiO3 spacer layers strongly affects the electronic properties of SrFeO3: for single SrFeO3 layers constrained to their bulk cubic structure, the Fermi surface is two dimensional, nested, and resembles that of the hole-doped superconducting cuprates. A Jahn-Teller instability couples to an octahedral tilt mode, however, to remove this degeneracy resulting in insulating superlattices....

[ Last edited by wxyuer on 2010-3-24 at 19:58 ]
13楼2010-03-24 19:52:09
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