Identification of Material Dimensionality Based on Force Constant Analysis

Abstract

Identification of low-dimensional structural units from the bulk atomic structure is a widely used approach for discovering new low-dimensional materials with new properties and applications. Such analysis is usually based solely on bond-length heuristics, whereas an analysis based on bond strengths would be physically more justified. Here, we study dimensionality classification based on the interatomic force constants of a structure with different approaches for selecting the bonded atoms. The implemented approaches are applied to the existing database of first-principles calculated force constants with a large variety of materials, and the results are analyzed by comparing them to those of several bond-length-based classification methods. Depending on the approach, they can either reproduce results from bond-length-based methods or provide complementary information. As an example of the latter, we managed to identify new non-van der Waals twodimensional material candidates.

Magnetic State Control of Non-van der Waals 2D Materials by Hydrogenation

“…Several magnetic representatives such as 2D hematene and ilmenene are derived from natural ores of transition metal oxides hematite (α-Fe 2 O 3 ) and ilmenite (FeTiO 3 ). These are complemented by various other compounds identified in experiments − and several dozens of systems suggested by recent data-driven investigations. − While these materials are also studied for their catalytic, , electrochemical, and optoelectronic properties, the magnetic features related to potential room temperature ferromagnetism and spin canting are attracting particular attention. ,,,− …”