State-selective excitation

The photodissociation of CHaONO(5i) reveals an intriguing quantum state selectivity excitation of NO(n ) in the complex preferentially yields NO fragments in vibrational state n — 1. 

Yamaguchi, T., Kimura, Y. and Hirota, N. (1998) Solvation state selective excitation in resonance Raman spectroscopy. II. Theoretical calculation. Journal of Chemical Physics, 109 (20), 9084-95. 

Soep and co-workers then investigated this system using Ca-HCl complexes [47]. Here, p-orbital orientation is controlled by state-selective excitation of complexes in the vicinity of the Ca Pi - So atomic transition. 

Heteronuclear coupling constants (1,b7c,h) are most commonly measured from heteronuclear 2D experiments. The 3/c H couplings can be easily extracted from /-resolved spectra as well as from f or F2 proton coupled HSQC spectra. The undesired evolution of "/CH during q can be eliminated with use of an appropriate bilinear rotation decoupling (BIRD) pulse, such as BIRDd,x in. /-resolved spectroscopy35 and 111RD in Fi-coupled HSQC.36 Spin-state selective excitation techniques, S3E and S3CT37 38 (spin-state-selective coherence transfer), can also be used for the measurement of... 

There are many useful tools to help focus attention on specifiable parts of the behavior of a many-body system, and many of these were listed in Section 9.1.4. The concepts of bright state, doorway state, and dark state, the experimental tools of state-selective excitation and detection, and the analysis tools of wavepackets and survival and transfer probabilities, can provide insights into the causes, preferred pathways, and possibilities for control of intramolecular dynamics. 

In direct detection experiments, several approaches were used to achieve virtual decoupling (to remove homonuclear one-bond carbon-carbon couplings) such as IPAP schemes (in-phase anti-phase) [150-152], in which two FIDs for each increment are recorded and stored separately, one for in-phase and another for antiphase, the two components being combined to remove the splitting. An alternative is S E schemes [152, 153] (spin-state selective excitation), in which two different experiments are performed with one being absorptive and another dispersive. One or more of these building blocks (IPAP and S E) can be implemented in any experiments based on direct detection. A set of based experiments, which can be used for the assignment of backbone and side-chains of labeled... 

Meissner A, Duus JO, S0rensen OW (1997) Integration of spin-state-selective excitation into 2D NMR correlation experiments with the heteronuclear ZQ/2Q pi rotations for Jxh resolved E.COSY-type measurements of heteronuclear coupling constants in proteins. J Biomol NMR 10 89-94... 

Fig. 3.13. Construction details of the combination of a temperature variable 22-pole ion trap and a pulsed supersonic beam. Primary ions are produced in a storage ion source and mass selected in a quadrupole mass filter (from the bottom, not shown). After deflection in an electrostatic quadrupole bender the ions are injected into the trap (see Fig. 3.12). There the ions are confined in radial direction by the rf field and in axial direction with dc voltages applied to the entrance and exit electrodes (less than 100 mV). Buffer gas is used, usually He, for thermalizing the ions. From the left a skimmed molecular beam traverses the trap without colliding with the cold surfaces. For detection, the stored ions are extracted to the right, mass selected and counted via a Daly detector. A laser beam can be injected via the detector tract for state selective excitation of the trapped ions.

T Yamaguchi, Y Kimura, N Hirota. Solvation state selective excitation in resonance Raman spectroscopy. 1. Experimental stndy of the C=N and C=0 stretching modes of phenol blue. J Chem Phys 109 9075, 1998. 

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