The synthesis of nanocrystalline ZnO by thermal decomposition of zinc hydroxyacetate, Zn-5(OH)(8)(CH3CO2)(2)center dot nH(2)O, was investigated. The decomposition process was examined using X-ray diffraction, thermogravimetric analysis, mass spectrometry, electron microscopy, Brunauer-Emmett-Teller surface area analysis, and solid-state NMR spectroscopy. Intermediate Zn-5(OH)(8)(CH3CO2)(2)center dot nH(2)O phases form at temperatures up to 110 degrees C from the starting compound Zn-5(OH)(8)(CH3CO2)(2)center dot 2H(2)O by partial dehydration. At similar to 110 degrees C, 4 equiv of ZnO and 1 equiv of Zn(CH3CO2)(2) are formed. Further heating causes Zn(CH3CO2)(2) to decompose to acetone, acetic acid, acetic anhydride, and ZnO. Notably, a portion of Zn(CH3CO2)(2) sublimes during the process. Overall, the product of the calcination is equiaxed ZnO nanocrystals of 20-100 nm diameter.