Betaarsenene

Betaarsenene, or beta arsenene (β-As), is a proposed two-dimensional allotrope of the element arsenic. It represents one of the predicted phases of arsenene, the two-dimensional form of arsenic, and is distinguished from other allotropes such as alpha-arsenene.

Structure and bonding: Beta-arsenene is described as a buckled or distorted honeycomb-like lattice in which arsenic atoms occupy two sublattices with alternating heights. This arrangement yields anisotropic in-plane properties and differs from the puckered structure associated with other arsenic phases. The exact lattice parameters and symmetry are model-dependent in theoretical studies.

Electronic and mechanical properties: Theoretical calculations suggest that monolayer beta-arsenene is a semiconductor with a finite band gap, the size of which can be influenced by strain, thickness, and chemical functionalization. Electronic transport is predicted to be anisotropic, reflecting the underlying lattice geometry. As a 2D material, beta-arsenene is also anticipated to exhibit notable mechanical stiffness and flexibility relative to its thickness.

Stability and synthesis: Beta-arsenene is predicted to be dynamically stable within certain computational models but is often described as metastable with respect to bulk arsenic. As of the current state of research, experimental realization has not been widely demonstrated, and synthesis remains a topic of ongoing investigation. Approaches discussed in the literature include epitaxial growth on suitable substrates or extraction from theoretically proposed bulk allotropes.

Potential applications: If synthesized, beta-arsenene could be explored for nanoelectronic and optoelectronic devices, as well as for integration into van der Waals heterostructures with other two-dimensional materials. The material’s tunable band gap and anisotropic properties offer potential advantages for strain-engineered or directionally dependent devices.