Point-charge calculations yield crystal field coefficients A(20)(R) in
R(3)(Fe, Ti)(29) of -285 K a(0)(-2) for the 4e site and + 191 K a(0)(
-2) for the 2a site. Bonding charge model calculations show that the N
-induced shift in A(20) is Delta A(20) = -187 K a(0)(-2) for R(3)(Fe,
Ti)(29)N-4.