Calculating Coordination Number for system having 2 atom types

Submitted by ishaandesai on Fri, 12/23/2016 - 11:27

Hello,

My objective was to calculate coordination number for each atom in a system having two atom types. I wanted to calculate the coordination number for same type atom contacts for both groups and different type atom contacts also.

I have used the following compute:

compute 1 all coord/atom along with the "mix - yes or no" option to get selective outputs for coordination number by contacts between atoms of different types.

However, LIGGGHTS does not compute neighbor contacts of atoms with same atom type even when "mix" keyword is stated "yes" . For two atom types A and B, Mix-yes should ideally give me A-A and B-B contacts but from manual calculations it is understood that "mix-yes" actually gives the number of A-B contacts. This contradicts the statements given in the documentation for compute coord/atom.

Please help.

Forums:

ckloss's picture

ckloss | Mon, 01/02/2017 - 13:57

Hi ishaandesai ,

thanks for raising this issue - we'll have a look before the next release

Christoph

aaigner's picture

aaigner | Wed, 01/11/2017 - 15:12

Hello ishaandesai,

Thanks again for your hint. With the next release we publish a corrected documentation.

As you noticed correctly, the 'mix yes' option calculated the coordination number for different atom types. In the next version this will still be the case, since this was the intended behaviour and the documentation was wrong.

Best wishes
Andreas