Exactly solvable spin-12 quantum chains with multispin interactions

A generalized spin-$\text{1}\text{2}$ quantum chain with m (n) spin interactions for the z (x) component of the spins is shown to be self-dual. Through duality, the m arbitrary, n = 2 version of the model is transformed into m independent Ising chains in a transverse field, allowing us to get the exact values of the critical exponents for any m (v = s = z = 1; β = m/8; n_x = m/4) and the spectrum. The anisotropic XY chain is a particular case with = 2.