Welcome to Cranium !!
Applicability: Cranium (core versions 0315+)

Welcome to Cranium – our advanced physical property management system. With Cranium you can:

  • Enter data for elements, chemicals and mixtures
  • Modify and extend existing estimation techniques
  • Draw new molecular structures for groups and chemicals
  • Estimate the physical properties of chemicals and mixtures
  • Control which techniques Cranium chooses for estimation
  • Evaluate the accuracy of estimation techniques
Cranium's Documents

Cranium’s goal is to provide you with powerful capabilities for storing, managing and analyzing physical property data and estimates. To accomplish this goal, Cranium uses five types of documents:

  • Knowledge Base Document: these are the core documents used to store information about chemicals, mixtures, estimation techniques, structural groups, elements and references. Cranium uses these documents to mange physical property data and estimate physical properties.
  • XY Graph Document: these documents are used to generate and manage two dimensional graphs.
  • Triangular Graph Document: these documents are used to generate and manage triangular graphs. Triangular graphs are often useful when analyzing composition dependent physical property values.
  • Bookmark Document: these documents enable you to store lists of entities, i.e., bookmarks. These entities can then be quickly accessed.
  • Report Document: these documents enable you to generate reports that can be printed, exported to word processors or posted on the internet.

Click on any of the above documents to view more details.

Reference Book Analogy

Each of Cranium’s documents was designed to be analogous to a common reference book. Each document is divided into chapters. Each chapter contains a number of pages. Information for a single chemical, mixture, technique, graph, bookmark, etc., is presented on each single page. Finding information in Cranium therefore typically involves “changing” chapters and "turning" pages.

Documents are divided into chapters - each tab at the top of the document's windows represents a difference chapter.
Each chapter is divided into pages. All the information for an entity, e.g., a chemical, mixture, technique, reference, etc., is stored on a single page.

Each document is displayed in a window which is divided into several "panes". The chapter pane, located at the window’s top, displays tabs representing each chapter contained in the current document. Clicking the left mouse button on any tab activates that chapter displaying information from one of its pages in the window.

Chapter Pane: each document is divided into chapters.
Identifier Pane: typically displays the name of the chemical, mixture, group, design, etc.
Data Pane: large window displaying data, estimates, graphs, notes, etc. on the current entity. (The Data Pane typically scrolls.)
Status Pane: displays the current page number and bookmark information.

Immediately below the chapter pane is the window’s identifier pane. This pane displays the identifier, typically a name, acronym, or abbreviation, which Cranium uses to find each entity.

The next pane is the data pane. This large, central window displays the bulk of data for each entity. The data pane is typically organized into sections with bold headings describing the presented information.

The status pane is located at the bottom of the window. The left half of the status pane presents the current page number as well as the total number of pages contained in the chapter. The right half of the status pane displays the bookmark being used by the current document.


Each Data Pane is divided into one or more Sections. Sections display data, estimates and information about one or more properties. The properties are typically related. For example, the image below a section for phase transition enthalpy properties, optical properties and temperature dependent properties.

Phase Transition Enthalpies Section: displays data, estimates and units for three properties.
Optical Properties Section: displays data and estimates for two properties. (Note that both refractive indices are dimensionless values so the units are displayed as empty boxes.)
Temperature Dependent Section: displays data, estimates, curves and equations for several temperature dependent properties. Each of these different values types is selected by clicking the left mouse button on the edit control to the right of the 'Property:' label. window displaying data, estimates, graphs,

Sections are "piece" used in reports, printing and throughout this documentation. For example, when you print a document you first select which sections to print.


Each Section is divied into one or more Fields. A Field typically displays information for one physical property. Fields contain one or more labels and data entry controls.

For example, the following image shows the Critical Properties Section. This section contains four fields: the critical temperature field; the critical pressure field (this field's label is covered by the number 1); the critical volume field; the critical compressibility field.

Field Label: each field will display one or more labels to identify the physical property being displayed and other relevant information. (This field's label, Pc, is covered by the number 1.)
Data Entry Control: displays data value or values for the field's property.
Estimates Control: displays an estimated value or values for the field's property.
Units Control: displays the units in which data values and estimates are shown.

For simplicity we usually refere to any kind of entry control as a data entry control. Thus the Data, Estimates and Units entry controls described above can all be called data entry controls.

A data entry control is typically a rectangular region used to display data, estimates, units, molecular structures, graphs, etc. Data entry controls always display blue text if they contain values than can be changed. Clicking the left mouse button anywhere within a data entry control will activate a data entry dialog.

Data Entry Dialogs

Cranium uses data entry dialogs to add and remove data from a document. For example, clicking the left mouse button on the Chemical Chapter’s critical pressure data entry control, denoted by the number 2 in the previous image, activates the following data entry dialog.

Using the dialog, you enter a value for the critical pressure, the units of measure, a reference typically indicating the source of the data, and comments. When you are finished and press the OK button Cranium checks your entered data’s validity and then updates the knowledge base.

Using this field-control-dialog approach for entering values has several advantages:

  • Cranium and Synapse can execute verification tests before accepting a data point. If an error is found the dialog can remain active allowing the offending value to be corrected.
  • A data point is entered into the knowledge base only after all associated values, e.g., temperature, pressure, datum and reference, are entered. This ensures knowledge base consistency.
  • Data entry dialogs can contain additional controls and tools to facilitate data entry. For example, pressing the List button in the previously shown dialog shows all the references contained in the current knowledge base.
Note: Original Units vs Displayed Units

The units in which data are entered and the units in which they are displayed in a field do not need to match. We recommend that all data are entered in their original units, e.g., the units reported in source reference document.

Related Documentation
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.