Orientation energy

FIGURE 13 3 (a) In the absence of an external magnetic field the nuclear spins of the protons are randomly oriented (b) In the presence of an external magnetic field Xq the nuclear spins are oriented so that the resulting nuclear magnetic moments are aligned either parallel or antiparallel to Xq The lower energy orientation is the one parallel to Xq and more nuclei have this orientation... 

Additionally, MO calculations indicate the lowest energy orientation occurs with the three strongest trans-influence ligands (two hydrides and a PPh3) in a facial configuration. Calculations on compounds IrX(CO)(PR3)2 indicates that weak donors X and strong 7r-acceptors PR3 favour addition in the XIrCO plane [134, 135],... 

FIGURE 5.4 A polar molecule rotating near another polar molecule spends more time in the low-energy orientations (shown shaded) that maximize attractions, and so the net interaction is attractive, but not as strong as it would be if the molecules were not rotating. 

Rate constant, rate law, concentration profile, experimental measurement, integrated rate laws, linear plots, half-lifes Theory of the rate constant (activation energy, orientation factor, collision frequency factor, Transition State Theory)... 

The IR measurements described in the previous section were performed in a normal incidence geometry on c-cut ZnO samples. Since the polarization of the light is perpendicular to the c axis, it follows that the O-H complexes that we observed are not aligned along the c axis. This observation contradicts some theoretical reports, which claim that the lowest energy orientation of the hydrogen is parallel to the c axis." The calculated energy differences are small, however, on the order of 0.1 eV. 

Which quantum numbers reveal information about the shape, energy, orientation, and size of orbitals ... 

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