Szajna, WojciechZachwieja, MirosławHakalla, RafałKępa, Ryszard2014-11-192014-11-192011-09Acta Phys. Pol. A 120, 417 – 423 (2011).05874246http://repozytorium.ur.edu.pl/handle/item/713The visible spectrum of AlH has been investigated at high resolution between 20000 and 21500 cm1 using a conventional spectroscopic technique. The AlH molecules were formed and excited in an aluminium hollow-cathode lamp with two anodes, filled with a mixture of Ne carried gas and a trace of NH 3. The emission from the discharge was observed with a plane grating spectrograph and recorded by a photomultiplier tube. The 0-0 and 1-1 bands of the C1Σ+-A1∏ system and 0-2 band of the A1∏-X1Σ+ were identified at 21126, 21368 and 20276 cm1, respectively. In total 121 transition wave numbers belonging to three bands were precisely measured (with accuracy of ±0.003 cm-1) and rotationally analysed. The new data were elaborated with the help of recent X1Σ+ state parameters reported by White et al. and of the C1Σ+, A1∏ states constants reported by Szajna and Zachwieja. As a result of this merged analysis the set of the molecular parameters and rotational terms values for the three lower lying states of the AlH molecule have been significantly improved.engHigh resolution molecular spectroscopyEmission spectroscopy of AlHX1Σ+A1ΠC1Σ+Emission spectroscopy of AlH: the X1Σ+, A1Π and C1Σ+ states characteristics.article