A new approach is reported for depositing crystalline germanium films. The deposition occurs at low temperatures (210-260 degrees C) via in situ disproportionation of GeI2 and is thereby useful for depositing Ge onto a wide range of surfaces. Deposition onto glass and polymer substrates is demonstrated. The rate of deposition onto glass is found to be 25 ng min(-1). New synthetic routes to GeI2, GeI4, and Cu3Ge are also reported. These are valuable precursors for the synthesis of germanium nanostructures and organogermanium compounds. (C) 2012 Elsevier Ltd. All rights reserved.