Analysis of the behavior of singlet pairs in inorganic crystal XOCl(X=Ti,Bi)

This article explore the behavior of singlet pairs in Inorganic crystals and take the Ti-Ti and Bi-Bi dimer for example, including the transition in critical temperture by directly or indirectly. Through the analysis, It is proposed that with the decrease of temperature, the strength of spin-orbit coupling (SOC) increases and the phase difference also increases. In the one-dimensional spin 1/2 chain system of TiOCl and BiOCl crystals, the possibility of reversible parameter modulation is proposed by the calculation of the first principle analyzing the process and analysis of the structural phase transition process. It's shown that the different sturcture transition is relate to the difference of the dimer structure and the fluctuation of orbital order through the comparative study of TiOCl and BiOCl.