Relaxationszeiten des Elektronenspins von Radikalen in einigen bestrahlten Aminosäuren bei 4,2 °K

Electron spin relaxation times of the irradiated amino acids acetyl valine, sarcosine, betaine, and glycine have been measured at 4.2 °K with two different methods. From the exponential decrease of signals due to saturation after rapid adjustment of the ESR spectrometer on resonance, the following spin-lattice relaxation times have been measured: acetyl valine T1= 0.2 sec, sarcosine T1=0.14 sec, betaine T1=0.07 sec, glycine T1 ∼ 0.3 sec. By the PORTIS saturation method the product T1 T2 was measured, and, T1 being known, the following spin-spin relaxation times T2 have been obtained: acetyl valine 2.1.10-9sec, sarcosine 1.10-9sec, betaine 9.10-10sec. All measured amino acids show the saturation behaviour of substances with “inhomogeneous” line broadening.