The phase field crystal (PFC) model describes crystal lattices at diffusive timescales. In its amplitude expansion (APFC), it can be applied to the investigation of relatively large systems under some approximations. However, crystal symmetries accessible within this method are limited to basic ones, namely triangular and square in two dimensions, and body-centered cubic and face-centered cubic in three dimensions. In this work, we propose a general description of virtually any lattice symmetry within the APFC model. To fully exploit the advantages of this model, featuring slowly-varying quantities in bulk and localized significant variations at dislocations and interfaces, we consider formulations suitable for real-space numerical methods. We explore approaches originally proposed for the PFC model which allow for symmetries beyond basic ones through extended parametrizations. Moreover, we tackle the modeling of non-Bravais lattices by introducing an amplitude expansion for lattices with a basis and further generalizations. We study and discuss the stability of selected, prototypical lattice symmetries. As pivotal examples, we show that the proposed approach allows for a coarse-grained description of the kagome lattice, exotic square arrangements, and the diamond lattice, as bulk crystals and, importantly, hosting dislocations.
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