Rubidium Chloride is an alkali metal halide with a chemical formula of RbCl. It is a white crystalline powder, soluble in water and slightly soluble in alcohol. In the gaseous state, RbCl is a diatomic molecule with a bond length of about 2.7868 Å. The bond length increases to 3.285 Å in the cubic crystal system, showing a high ion coordination number in the solid state. There are different applications in the fields of electrochemistry and molecular biology.
According to this condition, solid Rubidium Chloride exhibits three arrangements or polymorphs in holographic imaging: Rubidium Chloride octahedral NaCl is the most common. Cl and Rb are the most densely packed cubes, filling the octahedral holes in them. In this arrangement, both ions are six-coordinated. The lattice energy of this crystal form is only 3.2 kJ/mol lower than the following crystal form.
Rubidium Chloride cube type Under high temperature and high pressure, RbCl forms the structure of CsCl. Chloride ions surround the Rb in the center of the cube at the eight vertices of the cubic crystal system. This is the structure with the highest density of RbCl. Since a cube has eight vertices, the coordination number of the two ions is equal to 8. This is the highest possible coordination number for RbCl. Therefore, according to the radius ratio rule, cations will reach the maximum surface radius in this crystal form because the distance between anion and cation is the largest.
The tetrahedral form of the Sphalerite tetrahedral Rubidium Chloride is quite rare in the structural research results. However, the predicted value of the lattice energy of this type is about 40.0 kJ/mol smaller than the above structure.