Germanium, tin, lead alkoxides

Voigt [1705] prepared transparent Ge02 glasses on hydrolysis of Ge(OEt)4 the temperature of glass formation is about l(XfC lower in comparison with that used in conventional methods. On crystallization of amorphous oxide prepared on hydrolysis of Ge(OPri)4, a mixture of two phases, crystoballite and a-quartz, is formed. On further thermal treatment, phase transition of crystoballite to a-quartz occurs, while grinding in air results in the transition to a rutile-type structure on treatment at temperatures higher than 1050°C all phases are tranferredto a-quartz [1766]. 

Although hydrolysis of tin alkoxides and alkoxochlorides, especially in the mixture with indium alkoxides, is used extensively, such as forpreparation of conductive ITO (solid solution of indium and tin oxides) layers, only few fundamental works on hydrolysis of Sn(OR)4 are known, and they have been summarized in a comprehensive review [702], Bradley proved the formation of oligomeric molecules as first hydrolysis products of [Sn(OPri)4 PrOH]2 by 

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