Magnetometry and Mossbauer spectroscopy have been utilized to study th
e high-T(c) compounds RBa2Cu3O7, RBa2Cu4O8, R2CuO4, and Bi2Sr2CaCu2O8
and a wide variety of substituted systems. It was found that in all sy
stems, the substitution of elements leads to a suppression of supercon
ductivity (SC) and to an enhancement of antiferromagnetism (AF).