Fourier Transform Spectra of the E(2)Pi(u)-X(2)Pi(g)((3/2)) System of CuCl(2).

High-resolution Fourier transform spectra of the laser-induced fluorescence of (63)Cu(37)Cl(2) produced in a cell have been recorded following excitation of a single vibronic level of the E(2)Pi(u) electronic state. Fluorescence occurs in combination bands to a broad spread of levels in the ground electronic state. A global vibronic model is proposed for the ground state based on an effective Hamiltonian, which fits the experimental data (2782 fluorescence lines, lower state quantum numbers: v(1) = 0-6, v(2) = 0-2, v(3) = 0-6, and J = 4(1/2)-80(1/2)) to 0.019 cm(-1) rms error. Vibrational, rotational and Renner-Teller parameters are obtained (e.g., omega(2) = 95.195(36) cm(-1), B(e) = 0.055106(3) cm(-1), epsilon = -0.1893(28)). A revised value for the equilibrium internuclear distance Cu-Cl is deduced: r(e)(Cu-Cl) = 0.20341(3) nm. The energy diagram of vibronic levels in the ground state is plotted up to 4000 cm(-1). Copyright 2000 Academic Press.

On the 5d 1Pig --> 2 (1)Sigma+u and 5d 1Pig --> C 1Piu Fluorescence in 7Li2.

Following excitation of the 5d 1Pig Rydberg state of 7Li2 by optical-optical double resonance, fluorescence has been observed in the infrared region to the 2 (1)Sigma+u and C 1Piu states. Analysis of high-resolution Fourier transform spectra yields term energies and rotational constants of the lowest seven vibrational levels of the inner well of the 2 (1)Sigma+u "double minimum" state. The equilibrium term value and dissociation energy have been determined to be Te = 30101.45 +/- 0.12 cm-1 and De = 5621.3 +/- 0.2 cm-1. The v = 0 and 1 levels of the C 1Piu state have been analyzed, resulting in new values of Te = 30551.0 +/- 0.1 cm-1 and De = 7773.3 +/- 0.2 cm-1. Copyright 1998 Academic Press.

The High-Lying Vibrational Levels and Dissociation Energy of the a3Sigma+u State of 7Li2.

Perturbation-facilitated optical-optical double resonance (PFOODR) has been used to access the 2(3)Pig state of 7Li2 via the excitation scheme using two single-mode tunable lasers. The selected () mixed level provides a gateway through which the triplet manifold can be accessed. Fluorescence from single rovibrational levels of 2(3)Pig to the state was detected at high resolution using a Fourier transform spectrometer. Transitions to v = 0-9 in the state were observed, covering the potential well almost to the dissociation limit. The data were analyzed using a near dissociation expansion (NDE) technique and the resulting vibrational and rotational parameters were used to calculate a new RKR potential curve which reproduced the observed energy levels to within a rms error of 0.02 cm-1. The following parameters were obtained for the state: D0 = 301.829 +/- 0.015 cm-1, De = 333.69 +/- 0.10 cm-1, Te = 8183.12 +/- 0.12 cm-1. Copyright 1999 Academic Press.