Calculation of Structural Parameters and Lattice Dynamics for the Jahn-Teller Oxide La₂CuO₄*

Elastic properties of La2CuO4under pressure

“…Note that the Jahn-Teller energy contribution plays a very important role in the crystal structure formation of K 2 CuF 4 [9] which has the same layered perovskite structure as La 2 CuO 4 , discussed in this work. The Jahn-Teller energy contribution was also found to be important for the correct simulation of the structure and lattice dynamics of La 2 CuO 4 [10] and this term determined the difference in physical properties between La 2 CuO 4 and La 2 NiO 4 [11]. We think that taking into account the multi-body Jahn-Teller contribution to the crystal energy of La 2 CuO 4 is preferable from the physical point of view to describing the Jahn-Teller effect by including the anisotropic Cu 2+ -O 2− pair potential (see, for example, [12]) or by considering the scaled Cu 2+ -O 2− pair potential involving apical oxygen (see [5]) †.…”