[gmx-users] combination rules

[Shuangxing Dai]

Hello,
    I was wondering how to set up parameters for interactions between two different atoms A and B. Since for Gromacs parameters are defined to each kind of atom, I cannot specify parameters between A and B. For Buckingham potential, the rule was:
   A_ij=(A_ii * A_jj)^(1/2)
So anyone know how to specify this value while not using the combination rules?

I also have problem in installing xmgr. I use MacOSX 10.5.5. I type ./configure and got this error messege:
ecme222-96-dhcp:xmgr-4.1.2 ssx$ ./configure
creating cache ./config.cache
checking host system type... configure: error: can not guess host type; you must specify one

Anyone has encountered this before? 
Thank you.

Shuangxing Dai
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://maillist.sys.kth.se/pipermail/gromacs.org_gmx-users/attachments/20090218/473b59c9/attachment.html>