ChemSpider
free chemical structure database providing fast text and structure search access to over 43 million structures from hundreds of data sources.
....Chemical Engineering Information Exchange
....One Stop Portal for ChE Information
....Manually Edited ChE Directory
....Integrated Technical Forums
....Social Network Friendly Portal
....Aggregated Industry News
....Responsive & optimized for multi-devices
....Multi-lingual site supporting 12+ languages
....Integrated blog platform to share knowledge
....Supporting Professional Enrichment