Structure, Bonding & Material Type Synthlet

Electronegativity plus valency can be used to predict a binary material's structure, bonding & material type with good – but not perfect – accuracy using a semi-quantitative van Arkel-Ketelaar Triangle + Laing Tetrahedron. Read about the logic behind the model on the previous few pages of this web book.

    Have a play around...
Select a pair of elements from the two drop menus:

↓ ↓ ↓ ↓ ↓ ↓ ↓

↓ ↓ ↓ ↓ ↓ ↓ ↓

Beryllium:  Eneg = 1.57   Valency = 2 Fluorine:  Eneg = 3.98   Valency = 1
Calculated name: Beryllium fluoride
Electronegativity difference, Δχ = 2.41   Average Electronegativity, (χa + χb)/2 = 2.775
% Ionic = 76.6    % Covalent = 23.4    Stoichiometric Formula = BeF2

Calculated name: Beryllium fluoride

From The Chemical Thesaurus Database
More Information
Beryllium fluoride

The author holding a physical model of the truncated tetrahedron of structure, bonding & material type. Download, print, cut out & build your own:

Read more about the Binary Material synthlet on the previous two pages of this web book: the van Arkel-Ketelaar Triangle of Bonding and the Tetrahedron of Structure, Bonding & Material Type.

Yes, the synthlet does make mistakes. For example, the well known gas carbon dioxide, CO2, is predicted to be a network covalent material like sand: silicon dioxide, SiO2.

But the model is right more than 90% of the time... and it is the fact that the model does not always predict correctly that makes chemistry so facinating!

Laing Tetrahedron
Classification of Matter

© Mark R. Leach 1999-

Queries, Suggestions, Bugs, Errors, Typos...

If you have any:

Suggestions for links
Bug, typo or grammatical error reports about this page,

please contact Mark R. Leach, the author, using

This free, open access web book is an ongoing project and your input is appreciated.