RM1 is a feature of AMBER.
You may download an evaluation copy.
Excerpts from the Amber12 and AmberTools12 Reference Manuals:
Image
![amber12 rm1](/sites/default/files/2021-06/amber12-rm1.png)
...
Image
![amber qmtheory rm1](/sites/default/files/2021-06/amber-qmtheory-rm1.jpg)
You may download an evaluation copy.
Excerpts from the Amber12 and AmberTools12 Reference Manuals:
...