Illustrating NMR cross-polarization (CP) with a microcomputer

As a continuation of previous works. QuickBasic computer programs have been developed for the solution of the equations describing the transfer of polarization in a system of coupled spins. when spin-lock conditions are applied. The transfer is considered to take place through a simple model of dipolar spin-spin interactions. The presence of a randomly changing surrounding is modeled by the random number generator of a microcomputer. The discussed examples allow one to understand the effects of cross-polarization as a function of the correlation time tau(0), and to introduce the concept of spin temperature. (C) 1998 John Wiley & Sons. Inc.