Hello. I have a question about single point energy calculations in Avogadro1.98.1. Are they possible? I’m teaching an online computational chemistry course and previously used Avogadro 1.2.0 to do this.

For example, I have the students build a simple molecule such as water. They then optimize the geometry using the MMFF94 force field. Next, I have them set one of the O-H bond lengths to 1.1 Å, and recalculate the energy at that geometry, set the bond to 1.2 Å, calculate the energy, etc. They then do the same thing, varying the H-O-H angle. This allows the students by hand to map out the potential energy and from that estimate the force constants used in the force field.

The process I just described was easy in Avogadro 1.2.0. I don’t see a way to do it in Avogadro2, but I admit that I have just started using it because some students are having difficulty installing Avogadro 1.2.0 on Windows 11, and am looking for a solution or work-around. The only single point energy calculation that I see uses the LJ potential model and no other force fields are able to be selected. From the Open Babel option, the geometry can be optimized with a specified force field, but I do not see a way to calculate the energy at some fixed geometry.

(We also use the auto-optimize feature in Avogadro 1.2.0 for things like this: Molecular Modeling Basics: The AutoOpt tool in Avogadro, so I really hoped that Avogadro 1.2.0 would not have installation problems this semester.)

Anyway, thanks in advance for any assistance.