| Description |
The optical transitions of supersonically cooled OsN have been investigated in the range from 19 200 to 23 900 cm-1 using resonant two-photon ionization spectroscopy. More than 20 vibronic bands were observed, 17 of which were rotationally resolved and analyzed. The ground state is confirmed to be 2A5/2, deriving from the 1a2 2a2 1tc4 153 3a2 electronic configuration. The X 2A5/2 ground state rotational constant for 192Os14N was found to be B0 = 0.491 921(34) cm-1, giving r0 = 1.620 42(6) A (1o error limits). The observed bands were grouped into three band systems with Q' = 7/2 and four with Q' = 3/2, corresponding to the three 2®7/2 and four 2n 3/2 states expected from the 1a2 2a2 1tc4 153 3 a1 2ft1 and 1a2 2a2 1tc4 152 3a2 2a;1 electronic configurations. The optical spectrum of diatomic IrSi has been investigated for the first time, with transitions observed in the range from 17 200 to 23 850 cm-1 (581 - 419 nm). A rich spectrum has been recorded, consisting of 14 electronic band systems and a number of unclassified bands. Thirty-one bands have been investigated with rotational resolution, allowing the ground state to be identified as X2A5/2 arising from the 1o2 In4 2o2 1S3 3o2 configuration. The ground X2A5/2 state is characterized by AG1/2 = 533 cm-1 and r0 = 2.0899(1) A for the more abundant isotopic form, 193Ir28Si (57.8%). The measured excited electronic states have equilibrium bond lengths ranging from 2.17 to 2.25 A and vibrational frequencies ranging from 365 to 452 cm-1. The optical spectrum of the linear CuCCH molecule has been investigated for the first time, using resonant two-photon ionization spectroscopy employing ArF (193 nm) or F2 (157 nm) excimer radiation for photoionization. Scans over the range 19 40025 200 cm-1 were conducted, leading to the observation of three electronic band systems. These are identified as the [20.2] ~1 ^ X 1E+, the A 1E+ ^ X 1E+, and the [24.7] B 1n ^ X 1E+ systems, although only the first two have been rotationally resolved. The ~1 state is tentatively assigned as having 3n 1 symmetry, becoming optically accessible through spin-orbit interaction with the B 1n state. |
