Initial static susceptibilities of nonuniform and random Ising chains
  Within the conventional framework of standard linear response theory we have derived exact results for the initial static susceptibilities of nonuniform spin-1/2 Ising chains. The results obtained permit one to study regularly alternating-bond and random-bond Ising chains. The influence of several types of nonuniformity and disorder on the temperature dependence of the initial longitudinal and transverse static susceptibilities is discussed. 
Oleg Derzhko, Oles' Zaburannyi and J. W. Tucker