<html><body bgcolor="#FFFFFF"><div>All:</div><div><br></div><div>my apologies for not being specific but as Gerald says this only works correctly in the current developers version. You will certainly get incorrect answers with the current production version. </div><div><br></div><div>-Kirk<br><br>Sent from my iPhone</div><div><br>On Aug 10, 2011, at 4:31 PM, binjiang.nju <<a href="mailto:binjiang.nju@gmail.com">binjiang.nju@gmail.com</a>> wrote:<br><br></div><div></div><blockquote type="cite"><div><stationery>
<div>
<div><font color="#000000" size="3">Dear Gerald and Kirk,</font></div>
<div> </div>
<div>Many thanks for your reply. I finally use the procedure
hf/multi/hf(maxit=1)/uccsd-f12(orbital,ignore_error), which works fine now.
I'm also grateful for Gerald's alert about the ccsd energies with non-rhf
orbitals. I would like to do more test to check if the ccsd energies with this
strategy are correct.</div>
<div> </div>
<div>Best, Bin.</div>
<div align="left"><font color="#c0c0c0" size="2" face="Verdana">2011-08-10</font></div><font size="2" face="Verdana">
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<div><font color="#c0c0c0" size="2" face="Verdana"><span id="_FlashSignName">binjiang.nju</span></font></div></font>
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<div>发件人: Gerald Knizia <<a href="mailto:knizia@theochem.uni-stuttgart.de">knizia@theochem.uni-stuttgart.de</a>></div>
<div>发送时间: 2011-08-11 05:38</div>
<div>主 题: Re: [molpro-user] UCCSD-F12 with CASSCF orbitals</div>
<div>收件人: "binjiang.nju" <<a href="mailto:binjiang.nju@gmail.com">binjiang.nju@gmail.com</a>></div>
<div>抄 送: molpro-user <<a href="mailto:molpro-user@molpro.net">molpro-user@molpro.net</a>></div>
<div> </div>
<div> </div>
<div><br><br></div>
<div>binjiang.nju wrote: </div>
<div>> I am trying to do a uccsd(t) calculation with CASSCF orbitals in </div>
<div>> Molpro.2010.1, it will be useful when two quasi-degenerate states </div>
<div>> exist and sometimes improve the convergence, comparing to the </div>
<div>> uccsd(t)/hf strategy. </div>
<div>> </div>
<div>> It works fine when I use only normal uccsd(t) option, but it fails </div>
<div>> when I use uccsd(t)-f12 option. I have tried to change the basis set, </div>
<div>> active space, as well as the type of CASSCF orbitals (Natural, </div>
<div>> Canonical), all of these do not help. Then I find some information for </div>
<div>> such problem, but still no suitalbe answer. </div>
<div>> </div>
<div>> Gerald Knizia has mentioned that the F12 methods do request RHF </div>
<div>> reference functions, but he would try to fix this. (I cite his words </div>
<div>> in the following, hopefully he would not mind) </div>
<div> </div>
<div>I have semi-fixed this in the current development version (i.e., it is </div>
<div>there possible to use such orbitals now, but it requires some persuation </div>
<div>with rhf,maxit=1). However, this turned out to be more complicated than </div>
<div>anticipated, which is why I did not backport the changes to the </div>
<div>production version. In the current production version both CCSD-F12 </div>
<div>programs will give (different) wrong energies when used with non-HF </div>
<div>orbitals. I would prefer to leave this issue open until the next Molpro </div>
<div>production version (i.e., the one from the current development version, </div>
<div>where this will work automatically), unless there is very strong </div>
<div>interest in having this feature available. </div>
<div>-- </div>
<div>Gerald Knizia </div></div></stationery></div></blockquote></body></html>