---
configs:
- config_name: default
  data_files: "co/*.parquet"
- config_name: info
  data_files: "ds.parquet"
license: apache-2.0
tags:
- molecular dynamics
- mlip
- interatomic potential
pretty_name: QM-22 Methane
---
### <details><summary>Cite this dataset </summary>Nandi, A., Qu, C., and Bowman, J. M. _QM-22 Methane_. ColabFit, 2025. https://doi.org/10.60732/ca55415d</details>  
#### This dataset has been curated and formatted for the ColabFit Exchange  
#### This dataset is also available on the ColabFit Exchange:  
https://materials.colabfit.org/id/DS_0twwqpqjvftx_0  
#### Visit the ColabFit Exchange to search additional datasets by author, description, element content and more.  
https://materials.colabfit.org
<br><hr>  
# Dataset  Name  
QM-22 Methane  
### Description  
The Methane set of the QM-22 datasets. QM-22 consists of CHON molecules of 4-15 atoms, developed in counterpoint to the MD17 dataset, run at higher total energies (above 500 K) and with a broader configuration space.  
### Dataset authors  
Apurba Nandi, Chen Qu, Joel M. Bowman  
### Publication  
https://doi.org/10.1021/acs.jctc.9b00043  
### Original data link  
https://github.com/jmbowma/QM-22  
### License  
Apache-2.0  
### Number of unique molecular configurations  
9000  
### Number of atoms  
45000  
### Elements included  
C, H  
### Properties included  
energy, atomic forces  
<br>
<hr>  

# Usage  
- `ds.parquet` : Aggregated dataset information.  
- `co/` directory: Configuration rows each include a structure, calculated properties, and metadata.  
- `cs/` directory : Configuration sets are subsets of configurations grouped by some common characteristic. If `cs/` does not exist, no configurations sets have been defined for this dataset.  
- `cs_co_map/` directory : The mapping of configurations to configuration sets (if defined).  
<br>
#### ColabFit Exchange documentation includes descriptions of content and example code for parsing parquet files:  
- [Parquet parsing: example code](https://materials.colabfit.org/docs/how_to_use_parquet)  
- [Dataset info schema](https://materials.colabfit.org/docs/dataset_schema)  
- [Configuration schema](https://materials.colabfit.org/docs/configuration_schema)  
- [Configuration set schema](https://materials.colabfit.org/docs/configuration_set_schema)  
- [Configuration set to configuration mapping schema](https://materials.colabfit.org/docs/cs_co_mapping_schema)