Avoid negative optimization
the code get stuck in a weired way
The code is in https://code.itp.ac.cn/Osgood/openlam-hack/-/blob/main/src/relax.py#L65 where the relaxer is defined as https://code.itp.ac.cn/Osgood/openlam-hack/-/blob/main/src/relaxer.py#L76