High pressure studies using Diamond Anvil Cells were carried out in an
tiferromagnetic insulator transition metal iodides characterized by th
eir layered structure. Magnetic properties studied by I-129 Mossbauer
Spectroscopy, the equation of state obtained from X-ray diffraction an
d metal insulator transition deduced from R(T,P) provided a detailed a
nalysis of Mott insulators under the high pressure regime and the natu
re of the pressure induced Mott transition.