The Input.zip file contains Plumed input files to run Metadynamics and Multithermal-Multibaric simulations for alpha-Ga, beta-Ga and Ga-II. Structures extracted from the metadynamics simulation of the nucleation of alpha-Ga and beta-Ga are also given, in which nuclei with different sizes can be seen. The structures are used to perform seeding calculations. The RefCV_code.zip file contains the code (the cpp file should be included in the /src/multicolvar directory of Plumed) to calculate the collective variable. The NN_potential.zip file contains the NN potential obtained in this work.