Nuclear Magnetic Resonance Powder Patterns of the Second-Order Nuclear Quadrupole Interaction in Solids with Asymmetric Field Gradient

Abstract

Numerical calculations of the powder pattern of the central component shifted by the second‐order nuclear quadrupole interaction in solids have been performed for various values of the asymmetry parameter, η. Shape functions have been obtained in units of (ν_Q²/6ν_L) (a—¾) for η=0.1, 0.2, ···, 1.0, at 0.1 intervals. Also, positions of special points such as infinities and steps of the shape function have been determined as functions of η. Effects of the dipolar broadening of the single‐crystal resonance upon powder patterns have been estimated for the case of η=0.5. Influences of anisotropic magnetic shift were also discussed on powder patterns obtained experimentally. These relations are useful for simple and rapid determinations of η and ν_Q from the second‐order powder pattern.