No abstract

The laser-induced fluorescence of the [Formula: see text] and [Formula: see text] transitions of Na2 are analysed, using high resolution Fourier transform spectroscopy. Fixed-frequency ion-laser lines (4880 and 4765 Å (1 Å = 10−10 m) from Ar+ and 6471 and 4762 Å from Kr+) together with laser frequencies from a ring dye laser, using rhodamine 6 G with λ = 5781.22 and 5796.80 Å, were used to excite Na dimer in the gas phase. Twenty-eight series of [Formula: see text] and [Formula: see text] systems have been assigned and analysed, and the strong transitions are accompanied by numerous rotational relaxation lines. Molecular constants of the [Formula: see text] state were calculated with high precision from simultaneous least-squares fits to 1410 lines assigned to the A–X and B–X systems. These constants have been used to determine the Rydberg–Klein–Rees potential curve of the X ground state for vibrational levels up to ν = 62.

No abstract

Laser induced fluorescence spectra of separated isotope tellurium dimers, 130Te2 and 128Te2, have been recorded with high precision Fourier transform spectrometry. Fixed frequency argon ion and krypton ion exciting lines ranging from 5145 Å to 4067 Å have been used and 64 series in 130Te2 and 32 in 128Te2 have been assigned and analyzed. Transitions involving four upper states, A0u+, B0u+ and two states of 1u character, and three lower states, X0g+, X1g and b1Σg+, have been identified. The high sensitivity and excellent frequency calibration of Fourier transform spectrometry have been used to get information about high vibrational levels in the lower states and thence to derive, by simultaneous least squares fits to about 7800 lines in 130Te2 and 1100 lines in 128Te2, estimates of molecular constants valid over wide ranges of v. These have been used to determine RKR potentials and dissociation energies. The very small Ω-doubling constant in X1g has been measured and is shown to have the value expected for interaction solely with X0g+.The character of the states is discussed. There are many perturbations, and intensity distributions show that some transitions are hybrids with parallel and perpendicular components. A0u+ appears to derive from 3Πu and B0u+ from 3Σu-, while the lowest 1u state may be assigned to 3Π1,u. There is fragmentary evidence for a second 1u state in the same region. Among the low lying states of Te2, a1Δg remains to be observed.

High resolution Fourier spectrometry techniques have been used to study the A