Zeeman–quadrupole cross relaxation between two nuclear spin species

Abstract
We derive an expression for the rate τ−1IS of the cross relaxation between the Zeeman splitting of one nuclear spin species (I spins, I=1/2) and the quadrupole splitting of another spin species (S spins, S≳1/2) via the I–S dipolar interaction. We calculate τIS for the case of CFCL2–CFCL2 (I spins are 19F, and S spins are 35Cl and 37Cl) and compare the results with experimental data.