{"id":27733,"library":"fairchem-core","title":"FAIR-Chem Core","description":"fairchem-core is the core package of the FAIR Chemistry library, providing machine learning models (e.g., GemNet-OC, DimeNet++) for chemistry and materials science. Version 2.19.0 supports Python 3.11 to 3.13. The library is actively maintained and released every few months.","status":"active","version":"2.19.0","language":"python","source_language":"en","source_url":"https://github.com/FAIR-Chem/fairchem","tags":["chemistry","materials science","machine learning","neural networks","OC20"],"install":[{"cmd":"pip install fairchem-core","lang":"bash","label":"Standard install"}],"dependencies":[],"imports":[{"wrong":"from fairchem.core.datasets import OC20Dataset","symbol":"OC20Dataset","correct":"from fairchem.data.oc.datasets import OC20Dataset"}],"quickstart":{"code":"import torch\nfrom fairchem.core.models import GemNetOC\nfrom fairchem.core.datasets import OC20Dataset\n\ndataset = OC20Dataset(\"s2ef\", split=\"train\", subset=\"200k\", root=\"./data\")\nloader = torch.utils.data.DataLoader(dataset, batch_size=32, shuffle=True)\nmodel = GemNetOC()\noutput = model(next(iter(loader)))\nprint(output)","lang":"python","description":"Minimal example: load OC20 S2EF dataset, create a model, and run a forward pass."},"warnings":[{"fix":"Update imports to use `fairchem.core` instead of `fairchem`.","message":"The package structure changed from `fairchem` to `fairchem.core` in version 2.0. Code using `from fairchem import ...` will break.","severity":"breaking","affected_versions":"<2.0"},{"fix":"Install PyTorch with CUDA: `pip install torch --index-url https://download.pytorch.org/whl/cu118`","message":"Requires PyTorch with CUDA. CPU-only will fail if GPU expects CUDA tensors.","severity":"gotcha","affected_versions":">=2.0"},{"fix":"Use `OC20Dataset` with `task='oc22'` if available.","message":"The `OC22Dataset` is deprecated in favor of `OC20Dataset` with appropriate parameters.","severity":"deprecated","affected_versions":">=2.10"}],"env_vars":null,"search_vec":"'2.19.0':32 '3.11':35 '3.13':37 'activ':41 'chem':3 'chemistri':15,27,48 'core':4,7,10 'dimenet':25 'e.g':21 'everi':45 'fair':2,14 'fair-chem':1 'fairchem':6 'fairchem-cor':5 'gemnet':23 'gemnet-oc':22 'learn':19,52 'librari':16,39 'machin':18,51 'maintain':42 'materi':29,49 'model':20 'month':47 'network':54 'neural':53 'oc':24 'oc20':55 'packag':11 'provid':17 'python':34 'releas':44 'scienc':30,50 'support':33 'version':31","created_at":"2026-05-09T05:51:48.122305+00:00","updated_at":"2026-05-09T05:51:48.122305+00:00","problems":{"verify_error":"Traceback (most recent call last):\n  File \"<string>\", line 1, in <module>\nModuleNotFoundError: No module named 'fairchem.data'"},"ecosystem":"pypi","meta_description":null,"install_score":null,"quickstart_score":null,"quickstart_tag":null,"pypi_latest":null,"cli_name":"","cli_version":null,"type":"library","homepage":"https://opencatalystproject.org/","github":"https://github.com/facebookresearch/fairchem","docs":"https://fair-chem.github.io/","changelog":null,"pypi":"https://pypi.org/project/fairchem-core/","npm":null,"openapi_spec":null,"status_page":null,"smithery":null,"categories":["ai-ml"],"base_url":null,"auth_type":null,"provenance":{"verified_status":"import_fail","verified_at":"2026-07-03","last_verified":"2026-07-03","next_check":"2026-07-10","install_tag":null}}