Estimating the Stability of the Structure of MAX Phases of Ti3AlC2 – хBх Composition on the Basis of Quantum-Chemical Calculations

Quantum-chemical calculations (QCCs) are performed using the VASP program to determine the possibility of obtaining a MAX phase of Ti 3 AlC 2 – х В х (0.5 ≤ х ≤ 2) composition. It is shown that the isomorphic substitution of C atoms for B atoms destabilizes the system but does not destroy it. Theoretical X-ray patterns are calculated according to the QCC data. Differences between the X-ray patterns of Ti 3 AlC 2 and Ti 3 AlC 2 – х В х (0.5 ≤ х ≤ 2) crystals are revealed, by which the substitution of C atoms for B atoms can be proved.