Phase diagram of spin-12 quantum Heisenberg J1–J2J1–J2 antiferromagnet on the body-centered-cubic lattice in random phase approximation

•RPA method applied on J1–J2 Heisenberg antiferromagnet on a bcc lattice.•Magnon spectrum and thermodynamic properties are determined.•Agreement with previous results at both high and low temperatures.

Magnetic properties of spin 12J1–J2 Heisenberg antiferromagnet on the body centered cubic lattice are investigated. By using two-time temperature Green's functions, sublattice magnetization and critical temperature depending on the frustration ratio p=J2/J1p=J2/J1 are obtained in both stripe and Néel phases. The analysis of ground state sublattice magnetization and phase diagram indicates the critical end point at J2/J1=0.714J2/J1=0.714, in agreement with previous studies.