EXTRACTING MULTITENSOR SOLID-STATE NMR PARAMETERS FROM LINESHAPES

The derivation of a Hamiltonian describing the quadrupolar and chemica l-shift interactions is presented in terms of irreducible spherical-te nser algebra, Some potential ambiguities concerning the sign of the as ymmetry parameters, in this nomenclature, are identified and clarified , A more robust algorithm for handling the boundary conditions imposed by the constraints on asymmetry parameters is described and implement ed in a nonlinear-least-squares minimization procedure, In addition, a detailed account is given on a more efficient method for computing th e NMR lineshape, and protocols for the extraction of NMR parameters fr om solid-state lineshapes are introduced. (C) 1995 Academic Press, Inc .