  This work systematically investigates the spin glass behavior of the double
perovskite Ca2FeReO6. Building on previous studies, we have developed a formula
to quantify the ions distribution at B-site, incorporating the next-nearest
neighbor interactions. Employing molecular field theory and Monte Carlo
simulations, the influence of various arrangements of two B-site ions on
frustration effects was uncovered. B-site is segmented into a and b-site,
defining the number of nearest neighbors from Fea to Feb (and vice versa) as
Zx(Zy). The significant frustration effects occur when 1<Zx(or Zy)<3, with Zx
is not equal to Zy and also when Zx(or Zy) ~ 3 while Zy(or Zx) ~ 4. All of
these are reflected in the variations observed in ground state magnetization
and the Thermal Energy Step relation to Zx and Zy. The model proposed in this
work can be applied to most B-site disordered in perovskite systems and even to
other chemically disordered in frustrated systems.
