Subject: CRYSTAL03 -

From: "Ojwang, J.G.O." <j.g.o.ojwang >< tue.nl>
Date: Fri, 17 Jun 2005 18:47:55 +0200

Hi.
I somehow sorted out the LIM007 case for a different system. The
geometry was not correct!
What now bothers me about the present structure is that using a 
visualisation package I see something not resembling crystal at all!
Reasons why the geometry inputs cannot be wrong are: (i) I've used 
different sets of well documented theoretical and experimental 
geometrical inputs with the same result (ii) other geometries for other 
different structures, other space groups, are very much perfect and 
gives me the right crystals.
My guess is (i) there is a bug in the crystal03 code as pertains to 
space group 11, but I've been assured that crystal03 code space group is 
bugfree (ii) maybe the structure(Na3AlH6) was assigned the wrong space 
group.

The geometry I used are as follows:

(a =5.33, b=5.53, c=7.68, beta=90.103)(space group(P21/n) 11)
Al  0.0   0.0   0.0
Na  0.0   0.0   0.5
H 0.9897 0.4532 0.2535
H 0.2281 0.3307 0.5437
H 0.1608 0.2673 0.9366

I tried other different sets of geometrical inputs(experimental and 
theoretical) with the same results. The program calculates alright but 
the structure does not resemble a crystal at all. (Al should be six 
coordinates in H)

Well, let me hear your opinion.

Best Regards,
Ojwang'

BTW: What bothers me is (i) was the wrong space group assigned to 
Na3AlH6 or is there a bug in crystal03 code in so far as space group 11 
is concerned.

-----Original Message-----
From:	Computational Chemistry List on behalf of Huub van Dam
Sent:	Fri 6/17/2005 9:48 AM
To:	chemistry >< ccl.net
Cc:
Subject:	CCL:CRYSTAL03 - Help needed
Hi,

I have been informed by our local CRYSTAL experts that most likely your
input geometry is wrong. Alternatively you may have a very diffuse
function in your basis set. LIM007 refers to the number of lattice
vectors needed  to describe your system correctly. This number can get
exceedingly big if some atoms are too close together, or likewise if you 
use too diffuse functions for crystal calculations in your basis set.

Let me know if this does not solve your problems and I will progress it
further.

Best wishes,

     Huub

Ojwang, J.G.O. wrote:

>Dear CCLnetters,
>Has anyone had experience with Crystal03? I've tried to run a system 
but I get error messages to the effect that:
>(i) increase LIM007
>(ii) neighbour list too big increase LIMBEC
>Any idea how I can do this.
>Futrther when I try to run a supercel I get an error message that 'file 
size limit exceed'. How can i increase the limit of the file size.
>Waiting for an urgent response from any Crystal03 informed netter.
>
>Best Regards,
>Ojwang' JGO
>
>Eindhoven University of Technology,
>The Netherlands.
>

Huub van Dam                  email: h.j.j.vandam >< dl.ac.uk
CCLRC Daresbury Laboratory    phone: +44-1925-603933
Daresbury, Warrington           fax: +44-1925-603634
Cheshire, UK
WA4 4AD