Patent ID: 8283922

Claim:
A method for heteronuclear decoupling in magic-angle spinning nuclear magnetic resonance measurements of solid samples, the method comprising the steps of: a) applying a decoupling RF-pulse sequence with a nutation frequency ν 1 I on spins (I) of a first kind of nucleus; and b) applying an excitation pulse on spins (S) of a second kind of nucleus, which is different from the first kind of nucleus, wherein the decoupling RF-pulse sequence comprises m blocks of pulses, with m≧4, each block comprising an N-fold repetition of a pair of pulses (τ p ) x (τ p ) −x , (τ p ) y (τ p ) −y , (τ p ) −x (τ p ) x or (τ p ) −y (τ p ) y , wherein τ p , given in parentheses, is a pulse duration (τ p ) and x, −x, y, −y, given in subscripts, are pulse phases, wherein N>1 and N is an integer number, τ p being equal for all pulses, wherein the pulse phases of all pulses in the pulse pair of the (i+1)-th block are inverted with respect to the pulse pair of the i-th block, with i=1 . . . m−1 and i is an odd number, the pulses (τ p ) x , (τ p ) −x , (τ p ) y , (τ p ) −y within each pair (τ p ) x (τ p ) −x , (τ p ) y (τ p ) −y being phase inverted, and a phase shift of the pulses (τ p ) x , (τ p ) −x , (τ p ) y , (τ p ) −y is carried out after each j-th block, with j≦m, wherein j is an even number.