Hi,
I am currently using shell-dynamo md package. And it is some kind of a
higher version of moldy as it writes in its manual. So I decided to write here.
My problem is ,
I am using the Buckingham potential. This potential is included in the
program. If you have a potential that is not included in the program than
you have an other opportunity. That is the program "tabulate.f". By this
program you can use your own potential.This makes it a data of U-r. The main
programtakes it as a potential. That makes a lot easier.
So I decided to control my output g(r) etc. with the potential included
inside the program with the tabulate.
But when I try to use a Buckhingham type potential
A*exp(-r/q)-C/r**6-D/r**8
there appear an error message "separation too small" or "separation too
big" with the change of "rstep" data. Then I figure out that if I make the
D=0 then eveything is OK. This make me think of that the last term makes the
function too sharp. And this is what the program does not want
What is the problem ? What makes this? I also put in an other type of potential
A*exp()+B*exp()+C*exp()
it occures again. Is there a general solution for that?
thanks alot
Ph. D. Seckin D. Gunay
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