Double resonance with

Figure 11.7. (a) Radiofrequency/optical double resonance line observed for the A -doublet transition in the J = 8 level of the A ll state ofCS. The Stark field was zero [11], (b) Radiofrequency/ optical double resonance with a Stark field, showing the M = 8 and 7 resonances for J = 8. The frequency was fixed at 1124.4 MHz while the electric field was swept. 

The sub-Doppler nature of double resonance with single mode c.w. lasers has been used to resolve hyperfine structure in an infrared-optical study of NH2 (Amano et. al. 1982). A fluorescence cell was placed inside the cavity of a CO2/N2O laser and between the poles of a 15" electromagnet capable of fields up to 22 kG. A dye laser beam was introduced into the cell through a ZnSe mirror, and excited NH2 fluorescence through transitions to levels of the V2 = 9 or 10 states. At magnetic fields which Zeeman tuned into resonance vibration-rotation transitions within the excited state the population transfer changed... 

The experimental development of infrared-microwave double resonance was paralleled by the elaboration of the theoretical framework. For example, Shimizu published a theory of two-photon Lamb dips, and Takami theoretically described the optical-microwave double resonance with emphasis to fundamental aspects and the double resonance with microwave detection, and with optical detection. Detailed information on the theory of infrared-microwave double resonance can also be found in Refs. 216, 225-227. 

A modification of the NQ double resonance with coupled multiplets method has been proposed, which can be used for the measurement of the dipolar structure of NQR lines in the case of a strong dipolar inter-... 

Schweiger A, Giinthard HsH. 1981. Electron nuclear double-resonance with circularly polarized radio-fi equency fields (CP-ENDOR) theory and applications. Mol Phys 42 283-295. 

MB molecular beam electric resonance or microwave optical double resonance with molecular beam... 

Ernst RR (1966) Nuclear magnetic double resonance with an incoherent radio-frequency field. Journal of Chemical Physics 45 3845. 

Polarization transfer from H should give an enhancement factor of more than 20 and a further time saving because of the dependence on T, of However, coupling between silver and protons is not commonly observed because of the lability of silver complexes and the low value of y( ° Ag). In principle, such systems could be studied by H-l Ag double resonance with a further sensitivity advantage. For phosphine complexes, polarization transfer from P should be possible. Conversely, Colquhoun and McFarlane have combined P- Ag, H pseudo INDOR FT measurements with a two-dimensional display which separates the /( ° Ag P) mul-tiplets belonging to each silver-phosphine species. 

IR-UV double resonance also selective for S and C Reaction of both Isotopes with high selectivity (high fluence)... 

Allyl alcohol, CH2=CH—CH2OH (2-propen-l-ol) [107-18-6] is the simplest unsaturated alcohol. One hydrogen atom can easily be abstracted from the aHyhc methylene (—CH2—) to form a radical. Since the radical is stabilized by resonance with the C=C double bond, it is very difficult to get high molecular weight polymers by radical polymerization. In spite of the fact that aHyl alcohol has been produced commercially for some years (1), it has not found use as a monomer in large volumes as have other vinyl monomers. 

The allyl radical is better stabilized by resonance with the adjacent double bond than the cyanomethylene radical and is, therefore, less reactive. 

Electron nuclear double resonance of transition metal complexes with organic ligands. A. Schweiger, Struct. Bonding (Berlin), 1982, 51, 1-119 (294). 

In graphite each carbon atom is bound to three others in the same plane and here the assumption of inversion of a puckered layer is improbable, because of the number of atoms involved. A probable structure is one in which each carbon atom forms two single bonds and one double bond with other atoms. These three bonds should lie in a plane, with angles 109°28 and 125°16,l which are not far from 120°. Two single bonds and a double bond should be nearly as stable as four single bonds (in diamond), and the stability would be increased by the resonance terms arising from the shift of the double bond from one atom to another. But this problem and the closely related problem of the structure of aromatic nuclei demand a detailed discussion, perhaps along the lines indicated, before they can be considered to be solved. 

The complex might be best described by saying that each oxygen atom could form a double bond with the chromium atom with the. use of either one of its two 7t orbitals and the accompanying pair of electrons, extra stability being achieved through the resonance between the two kinds of double bonds. 

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