Rydberg states dipole moment

Abs absoiption transitions of cytosine in water experimental data for keto-N3H and imino tautomers correspond to 3-methylcytosine and 3-methylcytidine, respectively, obtained in aqueous solution at pH 11 [279], °ground state dipole moments of keto-N3H, imino and enol tautomers at the HF/6-311G(d,p) level are 8.15, 5.12 and 3.34 Debye, respectively, scaled (scaling factor 0.72) excitation energies, Rydberg contamination. 

When a) l/n3, the field required for ionization is E = 1/9n4, and as a> approaches l/n3 it falls to E=0.04n. These observations can be explained qualitatively in the following way. At low n, so that a> 1/n3, the microwave field induces transitions between the Stark states of the same n and m by means of the second order Stark effect. With only a first order Stark shift a state always has the same dipole moment and wavefunction, as indicated by the constant slope dW/d of the energy level curve. Thus when the field reverses, — — , the Rydberg electron s orbit does not change. With a second order Stark shift as well, the slope dW/d is not the same at E and —E, and as a result the dipole moment and wavefunction are not the same. If the field is reversed suddenly a single Stark state in the field E is projected onto several Stark states of the same n and m when E — - E. Since all the Stark states of the same n make transitions among themselves they ionize once the field is adequate to ionize one of them, the red one, at E = 1/9n4 for m n. 

Fig. 2). A relatively small basis set was used, but one that was capable of describing the Rydberg character of the C state. The AMfl-X E transition moment is well described by an SA-CASSCF procedure that includes the A13s and 3p and H Is orbitals in the CASSCF active space. As the C E" state is derived from the S(3s 4s ) state of Al, the active space must be expanded beyond the valence orbitals. When the 4s is added to the active space, all MRCI properties except the dipole moment of the C state are in good agreement with the FCI. Since the C E state is very diffuse, small...

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