Coarse-graining is a systematic way of reducing the number of degrees of freedom representing a system of interest. Several coarse-graining techniques have so far been developed, such as iterative Boltzmann inversion, force-matching, and inverse Monte Carlo. However, there is no unified framework that implements these methods and allows their direct comparison. We present a versatile object-oriented toolkit for coarse-graining applications (VOTCA) that implements these techniques and provides a flexible modular platform for the further development of coarse-graining techniques.
All methods are illustrated and compared by coarse-graining the SPCE water model, liquid methanol, liquid propane, and a single molecule of hexane.