Molecular nitrogen rotational energy

Rotational RT Relaxation. Using the Parker formula and data from Table 2-24, calculate the energy well depth of the intermolecular attraction potential T and the probability of RT Relaxation in pure molecular nitrogen at a translational gas temperature of 400 K. 

Basically, the rotational motion of the molecular species in the plasma is considered to be an approximate value to the gas translational temperature, which is the case for N2 C IIu and B sflg states as already shown in sections 2 and 3. However, the rotational temperature of INS is higher than those of IPS and 2PS, and consequently, it does not correspond to the translational temperature of neutral molecules. Similar results are reported on Tr of INS of low-pressure discharge nitrogen plasmas (Huang et al., 2008). These experimental results possibly indicate that the dominant population process of excited states B of N2 is not the direct excitation from the ground state of neutral N2 molecule, and not from excited states of neutral molecular state, either. Otherwise, the rotational energy distribution of N2 B 2Zu+ should become almost the same with the initial state of the molecule. 

The MM2 force field3 is probably the most extensively parameterized and intensively used force field to date. It reproduces a variety of molecular properties such as geometry, dipole moments, conformational energies, barriers to rotation and heats of formation. Of particular importance for calculations of amines is that MM2 treats lone pairs on sp3 nitrogens (and oxygens) as pseudo atoms with a special atom type and parameters. A closely related force field, MM2 7, was derived from MM2 by Osawa and Jaime. MM2 uses the same potential functions as MM2, but employs a different set of parameters in an attempt to better reproduce barriers to rotation about single C—C bonds. 

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