SnOx nanoparticles fabricated by gas-phase condensation and in-flight sintering were studied using Raman and luminescence (PL) spectroscopy. Various vibrational states of the rutile phase of the SnOx crystal were identified. By thorough anal. of the vibrational modes, the authors are able to det. the bond lengths of the O-O and Sn-O bonds for the substoichiometric SnO1.5, leading, together with x-ray diffraction data, to a full characterization of the SnO1.5 lattice. In absorption and luminescence, a finite d. of states was obsd. inside the band gap due to O vacancies, giving rise to a midgap luminescence peak. Probably the defect related luminescence efficiency is limited by nonradiative recombination processes and by the O vacancy d. The PL intensity has a max. around a stoichiometry of SnO1.7.