From owner-chemistry@ccl.net Wed Mar  2 13:49:00 2011
From: "Mike Edmund Miller really_mike###yahoo.com" <owner-chemistry^^server.ccl.net>
To: CCL
Subject: CCL: Boron NT fails with "Diagonalization in DiagDN via DSPEV failed"
Message-Id: <-44034-110302113018-4509-YpTkGrkpK+OLp4Fhu0z+dw^^server.ccl.net>
X-Original-From: "Mike Edmund Miller" <really_mike]~[yahoo.com>
Date: Wed, 2 Mar 2011 11:30:16 -0500


Sent to CCL by: "Mike Edmund Miller" [really_mike{:}yahoo.com]
Dear CCL members,
 A boron nanotube which I am trying to optimize fails as indicated in subject header. The route line for that job is:

#T Opt Freq=raman b3lyp/6-31g(d) scf=(NoVarAcc,maxcyc=9999) 

I included the "NoVarAcc" keyword in an attempt to solve the original error of "Inaccurate quadrature in CalDSu". Other unsuccessful attempts to deal with the inaccurate quadrature error included 1) another WF guess, i.e.,  "Guess=INDO" and 2) an ultrafine grid together with a opt=tight.

I have also tried tweaking the input coordinates manually.

Thank you for your ideas / guidance you could provide in this matter.
Mike