Ground state vibrational energy

The factor Dg can either be determined from the dissociation energy and the ground state vibration energy or from thermodynamic data. The heat of formation of H atoms from H2 molecules can be found in the literature, but some care should be exercised in considering the total energy content of H atoms and H2 molecules under standard conditions. 

Both Qj and Ax are in dimensionless units and therefore the force constants kj are equal to the excited state vibrational energies in wavenumbers. The latter are obtained from the spectrum (Fig. 10 and Table 1). The At denote the excited state distortions and are the parameters to be determined. The values of both E00 (22613 cm-1) and F(19 cm-1) are obtained from the spectrum in Fig. 10. The initial wavepacket 0 is calculated by using the literature values for the ground state vibrational energies along the 3 modes. 

We see that the minimnm threshold energy plus the ground-state vibrational energy, 12.09 kcal/mol, is the total energy required to cross over the barrier (9.13 kcal/mol) in order for a reaction to occur. This result indicates that all the gronnd-state vibrational energy is not available for reaction. In addition, the activation energy in the Arrhenius equation,... 

The force constant is a measure of the stiffness of a chemical bond. Larger values of k imply sharply curved potential energy functions and are often associated with deeper potential wells and stronger bonds. Molecular force constants are typically in the range of 200-2000 N/m, remarkably, not very different from those for bedsprings. From the solution for the harmonic oscillator, we identify the ground-state vibrational energy, with quantum number u = 0, as... 

Table 3 Energies of the resolved low-energy transitions in the absorption spectrum of the NITCN radical. Alphabetical labels are given in Fig. 5. Energy intervals AE are defined relative to the lowest-energy transition labeled a at 13236 cm-1. Raman shifts corresponding to ground-state vibrational energies are included for comparison. All values are in wavenumber units (cm-1)...

M. E. Jacox, Ground state vibrational energy levels of polyatomic transient molecules,/. Phys. Chem. Ref. Data, 13, 945,1984. 

The force constant is Oj is 1180 N/m. What is its expected vibrational frequency What is its expected ground-state vibrational energy ... 

The final term is the zero-point energy. We change the zero of potential energy so that the ground-state vibrational energy is equal to zero, and Eq. (25.1-4) becomes... 

Estimate the ground-state vibrational energy of H C1 using Equation 6-41 and the data in Table 6-2. How does this corr are to the ground vibrational energy of H C1 obtained in the same way What can you conclude about the effect of isotopic substitution and bonding ... 

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