Energy transfer electron spin resonance

Double-resonance spectroscopy involves the use of two different sources of radiation. In the context of EPR, these usually are a microwave and a radiowave or (less common) a microwave and another microwave. The two combinations were originally called ENDOR (electron nuclear double resonance) and ELDOR (electron electron double resonance), but the development of many variations on this theme has led to a wide spectrum of derived techniques and associated acronyms, such as ESEEM (electron spin echo envelope modulation), which is a pulsed variant of ENDOR, or DEER (double electron electron spin resonance), which is a pulsed variant of ELDOR. The basic principle involves the saturation (partially or wholly) of an EPR absorption and the subsequent transfer of spin energy to a different absorption by means of the second radiation, leading to the detection of the difference signal. The requirement of saturability implies operation at close to liquid helium, or even lower, temperatures, which, combined with long experimentation times, produces a... 

Force-field methods, calculation of molecular structure and energy by, 13,1 Free radical chain processes in aliphatic systems involving an electron-transfer reaction, 23, 271 Free radicals, and their reactions at low temperature using a rotating cryostat, study of, 8. I Free radicals, identification by electron spin resonance, 1, 284... 

Abstract The scattering process responsible for connecting the bands remains one of the last open questions on the physical properties of MgE. Through the analysis of the equilibrium and photo-induced far-infrared properties as well as electron spin resonance of MgB2 we propose a phonon mediated energy transfer process between the bands based on the coupling of quasiparticles to an E2g phonon. 

Possible electron transfer processes merit discussion, a priori, because of the relatively low solid-state ionization energy of the PDA backbone (2) and the strong acceptor character of bromine. Since the resultant products of bromination are largely diamagnetic, a long-lived electron transfer product is not involved. Moreover, when the bromination reaction is monitored by electron-spin resonance ( ), no buildup of a paramagnetic species was noted. In view of these observations, reaction via electron transfer as a major process is ruled out. 

An Electron Spin Resonance Study of Energy Transfer in the y-Irradiated System Benzene/Silica Gel... 

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