CRYSTAL03 -

["Ojwang, J.G.O." <j.g.o.ojwang >< tue.nl>]

 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