| 查看: 953 | 回复: 8 | ||
| 【奖励】 本帖被评价7次，作者zxzj05增加金币 6.5 个 | ||
| 当前主题已经存档。 | ||
[资源]
【分享】三类分子动力学
|
||
|
Classical Molecular Dynamics Simulation In classical molecular dynamics simulations, the classical interatomic potentials are used to crudely approximate the true quantum mechanical potentials since classical forces can be rapidly evaluated. State of the art classical molecular dynamics scheme can calculate the atoms with size up to multimillion atoms. Vashishta et al. constructed meaningful models of glassy GeSe2 and other amorphous materials. Tight-binding Molecular Dynamics Simulation Tight-binding molecular dynamics (TBMD) is designed to run moderate molecular dynamics simulation within the semi-empirical tight-binding scheme. The electronic structure of the simulated system is calculated by a TB hamiltonian so that the quantum mechanical many-body nature of the interatomic forces is naturally taken into account. Sankey and Allen used a tight binding Hamiltonian to do MD first in 1986. The best order N TBMD code now can calculate with size up to several thousand atoms. Ab initio Molecular Dynamics Simulation In mid eighties, Car and Parrinello showed how to combine the accuracy of ab initio density functional methods with force calculations and molecular dynamics techniques. In ab initio MD, the nuclei are treated as classical particles which move in a potential determined by the atomistic force calculated by the density functional theory due to Kohn, Hohenberg and Sham. Now, the state of art MD simulation can be applied for several hundred atoms. For ab initio method, the only information which must be provided are the atomic numbers and positions of the atoms within the system. In contrast, empirical or semi-empirical approaches require a model of the interactions between the atoms to be supplied. The parameters of these models are usually derived by fitting the outcome of simulations to experimental data. Problems with these techniques arise when one considers the range of their applicability. If the parameters of the models were derived from system A, what guarantee is there that they apply to system B with different chemical bonding and/or topology? In a disordered environment, it is very hard to find a universal set of parameters for the classical or semi-classical potentials. As a result, large numbers of fitting parameters are usually needed for either empirical potentials or tight-binding models. In this respect, ab initio MD in which the interatomic potential is determined by the electronic structure of the system is the method of choice to model complex amorphous materials. [ Last edited by fegg7502 on 2009-12-8 at 23:59 ] |
回复此楼» 猜你喜欢
重庆交大26年硕士生招生拟调剂通知已出！欢迎加入光子学微结构与器件课题组。
已经有0人回复
-
UJN物理学专业调剂
已经有12人回复
-
物理学I论文润色/翻译怎么收费?
已经有227人回复
-
0702一志愿吉大B区求调剂 本科期间发表一篇Sci
已经有0人回复
-
北京纳米能源与系统研究所王中林院士/曹南颖研究员课题组招收2026硕士研究生1名
已经有0人回复
-
山西大同大学物理学硕士研究生招收调剂生
已经有0人回复
-
[调剂信息]211智能人工感知方向国家青年特聘专家课题组招收调剂研究生
已经有0人回复
-
［调剂信息］211智能人工感知方向国家青年特聘专家课题组招收调剂研究生
已经有0人回复
-
[调剂信息]211智能人工感知方向国家青年特聘专家课题组招收调剂研究生
已经有0人回复
-
一志愿物理所凝聚态物理352求调剂
已经有0人回复
» 本主题相关商家推荐: (我也要在这里推广)
2楼2009-04-29 11:25:52
4楼2009-06-13 21:26:18
5楼2009-12-08 23:59:45
8楼2010-01-28 03:37:09
9楼2010-01-28 08:24:19
简单回复
2009-06-01 16:22
回复
mingdong6楼
2009-12-10 12:55
回复
cadick7楼
2010-01-28 00:15
回复
