مصادر الكيمياء موقع لتعليم الكيمياء بصورة مبسطة
A sequence of pulses used for spin-echo experiments in nuclear magnetic resonance (NMR) in which the initial pulse is 90° followed by a series of 180° pulses. A CPMG sequence is designed so that the spin echoes die away exponentially with time. Spin-spin relaxation occurs characterized by a time constant T2, which can be determined from the decay signal.