Magnetic properties of two copper (II)-halide layered perovskites

The magnetic properties of the powdered layered structures of 3‐ammoniumpyridinium tetrabromocuprate(II) and 3‐ammoniumpyridinium tetrachlorocuprate(II) have been studied from 4.2 to 150 K. The data were interpreted using both 1D and 2D series expansions for the Heisenberg model, combined with the appropriate mean‐field corrections, yielding interlayer exchanges with J2h/k values of (−11±2) K for the chloride salt and (−52±7) K for the bromide salt. The intralayer exchange (J1h/k) values were found to be (14±2) K and (20±2.5) K for the chloride and bromide salts, respectively. The new results are compared with previous results for the eclipsed layered structure series NH3(CH2)nNH3CuX4, where X=Br or Cl and n=2, 3, 4, or 5. As the halide‐halide separation distance decreases the transition from magnetic isolation of the layers to a strong interlayer exchange is observed. The new study allows confirmation of the power dependence on the halide‐halide separation.The magnetic properties of the powdered layered structures of 3‐ammoniumpyridinium tetrabromocuprate(II) and 3‐ammoniumpyridinium tetrachlorocuprate(II) have been studied from 4.2 to 150 K. The data were interpreted using both 1D and 2D series expansions for the Heisenberg model, combined with the appropriate mean‐field corrections, yielding interlayer exchanges with J2h/k values of (−11±2) K for the chloride salt and (−52±7) K for the bromide salt. The intralayer exchange (J1h/k) values were found to be (14±2) K and (20±2.5) K for the chloride and bromide salts, respectively. The new results are compared with previous results for the eclipsed layered structure series NH3(CH2)nNH3CuX4, where X=Br or Cl and n=2, 3, 4, or 5. As the halide‐halide separation distance decreases the transition from magnetic isolation of the layers to a strong interlayer exchange is observed. The new study allows confirmation of the power dependence on the halide‐halide separation.