pentagonalbipyramidal
Pentagonalbipyramidal refers to a geometric shape characterized by two pentagonal pyramids joined at their bases. This forms a polyhedron with ten triangular faces, seven vertices, and fifteen edges. Imagine two pentagons, one above the other, with their vertices connected to a central pentagonal plane. The resulting solid has a symmetrical structure. The term describes the overall shape and can be applied to molecules, crystal structures, or abstract geometric concepts. In molecular geometry, a pentagonalbipyramidal arrangement is a specific coordination geometry where a central atom is bonded to seven other atoms. This arrangement is less common than octahedral or tetrahedral geometries. The angles between the bonds in a pentagonalbipyramidal structure are not all equal, with equatorial bonds having slightly different angles than axial bonds. This geometry arises from the repulsion of electron pairs around a central atom, following VSEPR theory.