Relative stabilities of GanAsm(n + m <= 4), as well as their structural and vibrational properties, were computed and analysed using a CCSD(T) reference method since experimental data in this area are sparse or unknown. The cc-pVTZ basis set is used for n + m = 3 while the cc-pVTZ-PP one is employed for n + m = 4. With the aim of investigating larger clusters, we explored several DFT functionals able to mimic the reliable CCSD(T) approach. Among them, the PBEO/SBKJC+sp,d is the most efficient, since average differences of about 0.042 angstrom and 5.1 cm(-1) were obtained for bond lengths and fundamental vibrational frequencies, respectively. As further test, this model is used to investigate and revisit an experimental IR spectrum of GanAsm mixture previously published by Li et al. [S. Li, R.J. Van Zee, W. Weltner Jr., J. Chem. Phys. 97 (1993) 11393]. (C) 2008 Elsevier B.V. All rights reserved.