Optically detected magnetic resonance ODMR

Optically detected magnetic resonance (ODMR) has yielded valuable information about dynamics of long-lived pholoexcitations of conjugated polymers. The technique relies upon the paramagnetic interaction of excitations with an applied magnetic field. For a particle with non-zero spin, placed in a magnetic field, the Hamiltonian is ... 

Optically detected magnetic resonance (ODMR) studies of -iT-conjugated polymer-based hght emitting diodes (LEDs) J. Shinar Organic Electroluminescent Materials and Devices, S. Miyata and H.S. Nalwa, Eds., Gordon and Breach, Amsterdam, pp.177-202... 

D was determined by measuring the Ams = 2 EPR transition, where ms is the spin quantum number. Several years later, D and E were obtained directly by observation of the Ams = 1 EPR signals/33 1 In 1973, Zuclich et alP redetermined the triplet-state splitting parameters of tyrosine using optically detected magnetic resonance (ODMR) spectroscopy. 

The charged quasiparticles can be probed by electrical dc conductivity measurements (for polarons), magnetic susceptibility (for polarons and bipolarons), electron-spin resonance (ESR) (for polarons) and optical measurements (for polarons and bipolarons). As ESR is well suited for studying spin-carrying polarons, optical modification of the ESR (optically detected magnetic resonance ODMR) can be applied to link the emissive or absorbing properties of the polymer with its spin state. 

Optically Detected Magnetic Resonance (ODMR). The first optically detected magnetic resonance experiment was done using the 3Pi state of... 

Triplets, and most kinds of charge carriers (see Chapter 11, Section IV.C), have spin, so they can be monitored magnetically, and changes in their concentrations under various conditions can be investigated by methods such as optically detected magnetic resonance (ODMR). An example of such a method applied to CPs is presented in Ref. 140. 

In this section, results of three different experimental methods that have been apphed to Pd(2-thpy)2 are reported. Information from optically detected magnetic resonance (ODMR spectroscopy), microwave-recovery measurements, and phosphorescence microwave double resonance (PMDR spectroscopy) is presented. These methods complement each other to a large extent. The discussion presented here can be fimited to the basic impfications of the methods, since a comprehensive review by Max Glasbeek concerning these aspects is found in Volume 213 of this series [90] and a detailed report by Glasbeek, Yersin et al. [61] concerning Pd(2-thpy)2 has only recently been published. 

RIO Hoff, A.J. (1986) Optically detected magnetic resonance (ODMR) of triplet states in vivo. In Photosynthesis III. Photosynthetic Membranes. Encyclopedia of Plant Physiology, New Series, Vol. 19 (Arntzen, C.J. and Staehelin, L.A., eds.) pp. 400-421, Springer Verlag, Berlin. 

Optically-Detected Magnetic Resonance (ODMR) has provided magnetic and hyperfine parameters for excited states of defects in SiC. Since ODMR combines EPR with photoluminescence, it gives a link between the information provided by each experiment. In SiC, most of the publications describe donor- and acceptor-resonances detected on distant donor-acceptor-pair (DAP) recombination. As in the other experiments, interesting effects occur due to the different symmetries which arise from the polytypism of SiC. 

E.S.R. and Microwave Studies and Related Studies.—The recently demonstrated technique of triplet absorption detection of magnetic resonance (tadmr) has been used to determine intersystem crossing from individual spin levels of PH, ]- and [2H10]-anthracene and 3,4-benzpyrene triplets.22 Optically detected magnetic resonance (odmr) has been used to probe out-of-chain hopping of excitons in... 

Another crucial finding was the realization that rapid spin-lattice (Ti) relaxation in the high-symmetry cycloalkane radical cations precludes their detection with optically-detected magnetic resonance (ODMR) [39-48], the technique which was routinely used to study radical cations in radiolysis of hydrocarbons [38, 50]. For example, trans-decalin + isolated in room-temperature cyclohexane has Tj 7 ns [50] while typical solute radical cations have Ti 1 ps. Since it takes several tens of nanoseconds to flip the electron spin with the microwave radiation (which is required for the magnetic resonance detection) radical cations of some cycloalkanes cannot be detected by ODMR. 

Optically Detected Magnetic Resonance (ODMR) Studies of Ti-conjugated Polymer Films, Solutions, Blends, and Devices... 

Optically detected magnetic resonance (ODMR) studies of 7i-conjugated polymer films, solutions, blends and devices... 

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