The second major step is calculating the relevant properties for the set of structures produced in the previous step. This process begins by fragmenting the environment subsystem, or its inner part, into smaller, computationally manageable fragments. Next, the embedding parameters for each fragment are determined and assembled to produce the complete embedding potential. The parameters for the outer part, if present, can be taken from a non-polarizable force field. For solvents, the fragments simply correspond to individual solvent molecules. In contrast, environments containing large molecules, such as proteins, require a more sophisticated fragmentation approach. For each fragment, atom-centered multipoles and polarizabilities are calculated. This methodology has been shown to produce highly accurate embedding potentials across a wide range of systems and properties. Then, a constrained geometry optimization is performed in which the geometry of the core region is optimized while keeping the environmental atoms fixed. This preserves, to some degree, the temperature effects in the environment and its interaction with the core subsystem. The partial Hessian, partial dipole gradients, and partial polarizability gradients, all of which are derivatives with respect to the positions of the nuclei in the core region, are then calculated based on the geometry-optimized structures.