In a chemical selection, you specify a set of constraints on physical properties and/or molecular substructures and then Synapse examines every chemical in a selected knowledge base identifying those chemicals that satisfy the input constraints.

The Chemical Selections Chapter is found in chemical selection documents. The chapter stores constraints and selection results.

Section	Description
Source Knowledge Base Section	used to record the knowledge base that will be used as the source of all chemical candidates, physical property data and estimation techniques.
Constraints Section	contains one large field managing the storage and editing of the physical and structural constraints used to constrain the selected chemical candidates.
Candidates Section	displays the chemical candidates and their constraint evaluation results in tabular and graphical formats.
General Notes Section	used to store any general notes about the current selection. Often a brief summary of the selection's objective is entered in this field.
Associated Documents Section	used to store links to any documents associated with the current selection.

The Chemical Selections chapter has commands for reporting results and selecting chemicals. These commands are available from the chapter's Commands menu.

• Open Source Knowledge Base: opens the knowledge base stored in the source knowledge base section.
• Test Selection Constraints: enables you test the current constraints on a selected chemical candidate. The results are shown in the Chemical Candidate Dialog.
• Report Design Properties: activates the Report Properties Dialog that enables you to select selection attributes and results to add to an open Report Document.
• Save Chemicals Ranking: activates the Knowledge Base Chemicals Ranking Dialog . The dialog enables to store each candidate chemical's distance or index of a selection as undesignated data with the source knowledge base.
• Select Chemicals: activates the Chemical Selection dialog. Synapse will automatically estimate the physical properties of each chemical found in the source knowledge base, use these values to evaluate each design constraint and display the results in the selection dialog.

The menubar provides numerous other commands for navigation, bookmarking, file operations, units conversion, etc. See the documentation on Common Commands for details.

Topic	Description
Getting Started using Synapse	provides a quick tour of Synapse's capabilities including examples of chemical product design.
Getting Started using Cranium	provides a quick tour of Cranium's capabilities including a discussion of structure editing.
Estimating Chemical Properties	a short video demonstrating how to estimate the physical properties of chemicals using either Synapse or Cranium.
Estimating Mixture Properties	a short video demonstrating how to estimate the physical properties of mixtures using either Synapse or Cranium.