The unit cell of zeolite structures consists of:
Alumina octahedra only
Silica tetrahedra only
Alternating silica tetrahedra and alumina octahedra
Silica octahedra and alumina tetrahedra
The framework of zeolite structures is composed of interconnected silica tetrahedra and alumina octahedra
units. These units form the basic building blocks of the zeolite framework.