Crystal structures of A2FeCl5sdot;H2O (A=Rb+, Cs+) and field dependent superconducting susceptometer measurements

摘要

Crystal structures and low field principal crystal axis magnetic measurements are reported for the antiferromagnetic iron (III) salts A2FeCl5sdot;H2O; A=Rb+, Cs+. The two compounds undergo a zero field paramagnetic to antiferromagnetic phase transition at 6.5 K (A=Cs+) and 10.05 K (A=Rb+). The spin flop magnetic phase is observed in high field measurements. The magnetic fieldhyphen;temperature phase diagrams are reported. All magnetic measurements were recorded on a superconducting susceptometer. The bicritical points are 6.25 K, 14.5 kOe (A=Cs+), 9.75 K, 17.8 KOe (A=Rb+). Crystal data for Cs2FeCl5sdot;H2O: space groupCmcm,Z=4,a=7.442(3) Aring;,b=17.307(7) Aring;,c=8.077(7) Aring;,V=1040 Aring;3,R=5.2percnt;, 561 reflections. Crystal data for Rb2FeCl5sdot;H2O, space groupPnma,Z=4,a=13.825(4) Aring;,b=9.918(3) Aring;,c=7.100(2) Aring;,V=4.9 Aring;3, 5.7percnt;, 712 reflections.