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HMR issue with 1.2.0, fixed in 1.2.1
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Depiction of HMR Propyne MD failure reported for 1.2.0 (linked above).
It is to be noted that there was an error (or not) while building 1.0.0 where the force constants for both a single bond and triple bond were given the same value in SMIRNOFF99 FROSST, the initial force field port (force constants of 700 for both single bonds and triple bonds), and optimization didn’t help rectifying it down the line, which maybe due to priors penalizing large changes.
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With this starting point using Mod-seminario angles and bonds brings parameters to physically intuitive values, and perform as well as Sage on the industry benchmark set. They also pass all the canary tests for HMR, which were placed as guard rails for any future releases to not relapse into it again.
| Parsley 1.2 | Refit with MSM (A+B) + Sage (T+V) as starting points |
b24: [#6X2:1]-[#6X4:2] | 1.46 / 1298 | 1.49 / 658 |
b27: [#6X2:1]#[#6X2:2] | 1.22 / 823 | 1.21 / 2667 |
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