Specifying bonds

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1

Hi Users,

When setting up the bonds in the read_data, I noticed a bond is only specified once, for example:

bonds

1 3 1 7
2 2 1 3
3 1 1 2
4 4 2 5
5 4 2 6
6 4 2 4

In this case bond 3 between atom 1 and atom 2 is only specified once…you do not see:

bonds

1 3 1 7
2 2 1 3
3 1 1 2
4 1 2 1
5 4 2 5
6 4 2 6
7 4 2 4

I understand that you you really only need to name the bond once but is it OK to name the bond twice as in the second case?

Thanks,
Joe

2

Hi Users,

When setting up the bonds in the read_data, I noticed a bond is only
specified once, for example:

bonds

 1   3      1      7
 2   2      1      3
 3   1      1      2
 4   4      2      5
 5   4      2      6
 6   4      2      4

In this case bond 3 between atom 1 and atom 2 is only specified once...you
do not see:

bonds

 1   3      1      7
 2   2      1      3
 3   1      1      2
 4   1      2      1
 5   4      2      5
 6   4      2      6
 7   4      2      4

I understand that you you really only need to name the bond once but is it
OK to name the bond twice as in the second case?

why don't you just make an experiment
and see, if it makes a difference?

i have not looked at the code, but i would
expect it does. i would expect that the
interaction will be calculated twice.

cheers,
     axel.

3

I understand that you you really only need to name the bond once but is it
OK to name the bond twice as in the second case?

no, it is not. That would make 2 bonds between those atoms, which
you likely do not want.

Steve