| Abstract Scope |
Monoclinic ferroelectric phases are used for understanding of functional perovskites. These phases play enhance such properties as dielectricity and piezoelectricity through polarization rotation and modification of domain microstructures. Such microstructures remain poorly understood given the complexity of the subject.
We formulate the geometrical laws governing the mesoscopic patterns of monoclinic ferroelectric domains. We catalog permissible domain walls (PDW) between such domains with “PDW” pertaining to domain wall, connecting two “strain” domains without lattice mismatch. We found that 12 monoclinic domains may connect along 84 PWD, including 48 with fixed Miller indices and 36 whose orientation depends on the free lattice parameters. We provide analytical expressions for the PDWs orientation, the matrices of transformation between crystallographic basis vectors and the separation between Bragg peaks, diffracted from each of the 84 pairs of domains.
The results help facilitate investigation of complex monoclinic domain microstructures, using X-ray or electron diffraction.
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