| 查看: 423 | 回复: 0 | ||
[交流]
【求助】关于分子动力学模拟中系统大小选取的问题
|
|
在GULP教程中有这样一句话,我理解不了,还请各位帮忙解释一下说的是什么意思,看文中的似乎是不能只取原胞,这是很容易理解的,也是肯定不能选那么小的,但是到底分子动力学模拟中系统大小应该如何选取呢,还有哪些因素需要考虑到呢,和声子的 k=(0,0,0) 又有什么关系呢? The other key issue is the size of the system to be simulated. A lot of systems can be described by a primitive cell (the assymetric unit). However, running MD on this cell would be meaningless - every cell of the crystal would be moving perfectly in phase which is not physical. In fact, using a single unit cell is just the same as sampling the phonons at just the k=(0,0,0) point - this is the point at which all cells are in phase. 感觉这个问题似乎不是只针对GULP才有的,是所有做分子动力学模拟都需要考虑的问题,所以放在这个版块里,还希望各位大侠可以多指教。 [ Last edited by ghcacj on 2010-12-20 at 15:46 ] |










回复此楼