Structure searching in CAS Online using STN Express:
An introductory workshop

Building structures: System defaults

• Build the basic structure
• What you draw is what you get
• Need to override system defaults so that what you see is what you want
• Block substitution to get more specific structures
  • Add hydrogens
  • Specify bond values
  • Use refinement filters
• Increase variability to get more generic structures
  • System-defined variables
  • Variable point of attachment
  • G-groups
  • Bonds