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  2. Cross-polarization - Wikipedia

    en.wikipedia.org/wiki/Cross-polarization

    Cross-polarization (CP), originally published as proton-enhanced nuclear induction spectroscopy (PENIS) [1] [2] is a solid-state nuclear magnetic resonance (ssNMR) technique to transfer nuclear magnetization from different types of nuclei via heteronuclear dipolar interactions.

  3. Electronic counter-countermeasure - Wikipedia

    en.wikipedia.org/wiki/Electronic_counter...

    Polarization can be used to filter out unwanted signals, such as jamming. If a jammer and receiver do not have the same polarization, the jamming signal will incur a loss that reduces its effectiveness. The four basic polarizations are linear horizontal, linear vertical, right-hand circular, and left-hand circular.

  4. COSMO solvation model - Wikipedia

    en.wikipedia.org/wiki/COSMO_solvation_model

    COSMO [1] [2] (COnductor-like Screening MOdel) is a calculation method for determining the electrostatic interaction of a molecule with a solvent. COSMO is a dielectric continuum model [1] [3] [4] [5] (a.k.a. continuum solvation model). These models can be used in computational chemistry to model solvation effects. COSMO has become a popular ...

  5. Nuclear Overhauser effect - Wikipedia

    en.wikipedia.org/wiki/Nuclear_Overhauser_effect

    Nuclear Overhauser Effect Spectroscopy (NOESY) is a 2D NMR spectroscopic method used to identify nuclear spins undergoing cross-relaxation and to measure their cross-relaxation rates. Since 1 H dipole-dipole couplings provide the primary means of cross-relaxation for organic molecules in solution, spins undergoing cross-relaxation are those ...

  6. Cross-polarized wave generation - Wikipedia

    en.wikipedia.org/wiki/Cross-polarized_wave...

    Consider the case of interaction of two perpendicularly polarized waves in nonlinear media with cubic nonlinearity. [1] The equations describing the self phase modulation of the fundamental wave A and the generation of new wave perpendicularly polarized wave B in condition that |B| << |A| (i.e. when the depletion of the fundamental wave is neglected, self and cross phase modulation of wave B ...

  7. Umpolung - Wikipedia

    en.wikipedia.org/wiki/Umpolung

    Dithiane chemistry is a classic example of polarity inversion. This can be observed in the Corey-Seebach reaction. Ordinarily the oxygen atom in the carbonyl group is more electronegative than the carbon atom and therefore the carbonyl group reacts as an electrophile at carbon.

  8. Ab initio quantum chemistry methods - Wikipedia

    en.wikipedia.org/wiki/Ab_initio_quantum...

    Ab initio quantum chemistry methods are a class of computational chemistry techniques based on quantum chemistry that aim to solve the electronic Schrödinger equation. [1] Ab initio means "from first principles" or "from the beginning", meaning using only physical constants [ 2 ] and the positions and number of electrons in the system as input.

  9. Polarizable continuum model - Wikipedia

    en.wikipedia.org/wiki/Polarizable_continuum_model

    The polarizable continuum model (PCM) is a commonly used method in computational chemistry to model solvation effects. If it is necessary to consider each solvent molecule as a separate molecule, the computational cost of modeling a solvent-mediated chemical reaction would grow prohibitively high.