Investigation and application of quantitative relationship between sp energy levels of Bi ³⁺ ion and host lattice

Information on ¹S ₀- ³P ₁ (A band) and ¹S ₀- ¹P ₁ (C band) transition energy of Bi ³ ion in dozens of different compounds has been gathered and analyzed. With the use of the dielectric theory of the chemical bond for complex crystals, relationships between A and C absorption band and environmental factor h _e were established: E _A=2.9726.206exp (-h _e/0.551); E _C=3.23610.924exp (-h _e/0.644). For Bi ³ doped hosts with known structure and refractive index, it is possible to predict Bi ³ energy level position with an good accuracy of typically ±0.51 eV using the two relationships. Moreover, a direct relationship between A and C band was deduced: E _C=3.2362.290(E _A-2.972) ^0.856. Thus a very simple method to predict C band position was proposed. This work will be of great help to understand spectroscopy of Bi ³ and will be useful for developing new PDP, LED and mercury-free fluorescent lamp phosphors.