The MARTINI force field is a coarse-grained model developed by the University of Groningen for biomolecular simulations. It improves upon previous models by increasing the number of interaction levels and particle types, allowing for more accurate representation of chemical compounds. The model is parametrized based on the reproduction of partitioning free energies between polar and apolar phases of various chemical compounds. It is applied to lipid bilayers, showing improved behavior in terms of stress profiles and pore formation. The model also allows for the simulation of planar ring compounds, including sterols. The new force field, named MARTINI 2.0, is designed for a broad range of applications without requiring reparametrization. It includes a detailed mapping of interaction sites, with different levels of interaction energy and particle types. The model uses a shifted Lennard-Jones potential for nonbonded interactions and a Coulombic potential for charged groups. It also includes specialized particle types for ring structures and antifreeze particles to prevent unwanted freezing of water. The model has been validated against experimental data and atomistic simulations, showing good agreement in terms of thermodynamic properties and phase behavior. The MARTINI force field is efficient and accurate, enabling the simulation of complex biomolecular systems at a reduced computational cost.The MARTINI force field is a coarse-grained model developed by the University of Groningen for biomolecular simulations. It improves upon previous models by increasing the number of interaction levels and particle types, allowing for more accurate representation of chemical compounds. The model is parametrized based on the reproduction of partitioning free energies between polar and apolar phases of various chemical compounds. It is applied to lipid bilayers, showing improved behavior in terms of stress profiles and pore formation. The model also allows for the simulation of planar ring compounds, including sterols. The new force field, named MARTINI 2.0, is designed for a broad range of applications without requiring reparametrization. It includes a detailed mapping of interaction sites, with different levels of interaction energy and particle types. The model uses a shifted Lennard-Jones potential for nonbonded interactions and a Coulombic potential for charged groups. It also includes specialized particle types for ring structures and antifreeze particles to prevent unwanted freezing of water. The model has been validated against experimental data and atomistic simulations, showing good agreement in terms of thermodynamic properties and phase behavior. The MARTINI force field is efficient and accurate, enabling the simulation of complex biomolecular systems at a reduced computational cost.