Periodic Boundary Conditions in Gaussian
- From: freddie salsbury <salsbufr.-at-.wfu.edu>
- Organization: Wake Forest University
- Subject: Periodic Boundary Conditions in Gaussian
- Date: Wed, 31 Dec 2003 13:12:12 -0500
Dear CCler's --
About 1 month ago, I asked if anyone has had much success in G03 with
PBC, because we seem unable to run a routine calc with diamond in 3D.
Since they we have discovered that 1 or 2D calculations work fine, its
just in 3D that things seem to break down.
Has anyone succesfully ran a 3D calc with the PBC code in gaussian and
with HF? If so would you share with us the input file? The one we've
been using is attached below, along with our results.
thanks for any assistance,
cheers
Fred
-------------------------------
%chk=diamond2G.chk
%mem=1024MB
#HF/STO-3G PBC(NKPoint=48,CellRange=20) Pop(Full)
diamond test
0 1
C 0.445875 0.445875 0.445875
C -0.445875 -0.445875 -0.445875
TV 1.7835 1.7835 0.0000
TV 1.7835 0.0000 1.7835
TV 0.0000 1.7835 1.7835
----------------------------------
First, the gaussian output says it turns symmetry off (even if you turn
it on, it cannot identify any symmetry).
We varied the CellRange from 20 to 50 and obtained the following results:
NClRep
CellRange Energy Time (min) MaxNCR NMtPBC Convg
10 -74.8774038316 8.01 285 285 0.3482D-04
15 -74.8788470298 7.40 591 591 0.3388D-04
20 -79.7834971028 335.50 1357 1357 0.1513D-02
25 -77.9532971257 47.78 1717 2179 0.1892D-05
30 -78.4667709573 26.46 1721 3185 0.1067D-04
35 -78.8229423341 32.52 1721 4501 0.7331D-05
40 -78.9686326165 43.85 1721 6775 0.2602D-05
45 -86.8332484908 1479.41 1721 8903 0.2117D-03
50 -83.4676895141 1724.68 1721 11387(convergence failure)
(the Cellrange=50 ended with an abnormal termination due to failure to
converge)
The ones that took a long time to run (20 and 45) not only had large
Convg values in the SCF, but also in the population analysis had
inequivalent carbons.
Dr. Freddie Salsbury, Jr.
Assistant Professor
Department of Physics
Wake Forest University
Winston Salem, NC 27109
http://www.wfu.edu/~salsbufr
http://csb.wfu.edu/(Center for
Structural Biology)