Fourier transform infrared (FTIR) monitoring of the Pb(C11H19O2)(2)-Zr(C9H15O2)(4)-i(Oi-C3H7)(2)(C11H19O2)(2)-O-2 system diluted in C8H18 solvent and used to fabricate MOCVD-Pb(Zr,Ti)O-3 films was investigated. No obvious gas-phase reactions between the sources and the C8H18 were detected. Analysis of the FTIR spectra of single source supply and of mixtures after removing the C8H18 spectrum showed that FTIR concentration monitoring was able to measure the concentration of source gases in a mixture by identifying the characteristic FTIR peaks. (c) 2007 Elsevier B.V. All rights reserved.