How to set and display the bond order in Builder of VNL 2015

[reallusion]

How to set and display the bond order in Builder of VNL 2015.
Thank you!

[Jess Wellendorff]

This is currently not possible, but we will consider it a user request for upcoming releases. Thanks!

[Anders Blom]

Note that bond order is not immediately a concept that is
a) relevant
b) defined a priori
at least if we talk DFT. Sure, we know some molecules contain "double bonds" etc, but that's really just to draw pretty pictures. If you truly want to know the bond order of a real system, you need first to perform the electronic structure calculation, and then analyze the results. Actually you can today already compute "Mulliken bond population" between pairs of atoms with ATK, it's not the same necessarily as the chemical bond order, but can give some insight into the bonding nature of different atoms.

On the other hand, also do note that bonds in general are not used in a DFT calculation, only the positions of the atoms matter in terms of input (and output) of the calculation. So whether or not a bond is drawn between two atoms in the Builder or Viewer, the calculation is not affected.

[reallusion]

Thanks for the reply.
Another quetion is How to add H+ or OH- ions in the Builder of VNL 2015 to simulate acidic or alkaline solutions.

[reallusion]

How to add H+ or OH- ions in the Builder of VNL 2015 to simulate acidic or alkaline solutions?

[Jess Wellendorff]

I think this depends a bit on what you want to achieve, but in general you do not specify exactly which atoms should be in a particular charge state. Instead, you can specify an overall non-zero charge state of your system, e.g. +2e. This works for Bulk and Molecular configurations.