[adf-list] EDA计算关于不受限制的开放壳系统

Erik van Lenthe. vanlenthe在scm.com.
星期四9月30日11:11:42 2016年

Dear Yini Zuo,

Please read the ADF Manual:

The fragments from which the molecule is built must be spin-restricted, 
that is: the fragment files must be result files of spin-restricted 
For purposes of analysis, however, it may be desirable in some 
applications to build your molecule from unrestricted fragments. This 
can be simulated as follows.

You tell ADF that you want to treat the fragments as if they were 
unrestricted; this causes the program to duplicate the one-electron 
orbitals of the fragment: one set for spin-α and one set for spin-β. You 
can then specify occupation numbers for these spin-unrestricted 
fragments, and occupy spin-α orbitals differently from spin-β  orbitals.

Of course, the unrestricted fragments that you use in this way, are not 
self-consistent: different numbers of spin-α  and spin-β electrons 
usually result in different spatial orbitals and different energy 
eigenvalues for spin-α and spin-β when you go to self-consistency, while 
here you have spatially identical fragment orbitals.
Nevertheless it is often a fair approximation which gives you a 
considerable extension of analysis possibilities.

Example: Bond Energy analysis open-shell fragments: PCCP:

Best regards,
Erik van Lenthe
> Dear sir,
>       It's my honor for your reading this letter. I'm Yini Zuo, a 
> postgraduate student of Sichuan University in Sichuan, China. I'm 
> writing to gain more information about the Energy-decomposition 
> ananlysis(EDA) calculation using ADF programme package. I'm 
> investigating a unrestricted open-shell system, and I want to do a 
> series of EDA calculation, but I hear of the impossibility of 
> unreatricrted EDA. So I wanna kown whether my system isn't suited 
> to the EDA analysis? How can I solve this problem?
>   Thanks for your time. I'm looking forward to your reply.
> 2016-09-30