# Isogonal

### From Online Dictionary of Crystallography

##### Revision as of 16:45, 5 October 2017 by MassimoNespolo (talk | contribs) (Created page with "<font color="blue">Isogonal</font> (''Fr''); <font color="red">Isogonal</font> (''Ge''); <font color="black">Isogonale</font> (''It''); <font color="purple">等角の</font> (''J...")

Isogonal (*Fr*); Isogonal (*Ge*); Isogonale (*It*); 等角の (*Ja*); Изогональная (*Ru*); Isogonale (*Sp*).

**Isogonal** is a mathematical term which means *having similar angles*. In geometry, a polytope is isogonal or **vertex-transitive** if all its vertices are equivalent, *i*.*e*. if each vertex is surrounded by the same kinds of face in the same or reverse order, and with the same angles between corresponding faces.

In crystallography, the term **isogonal** has been introduced by Buerger to indicate isometries characterized by the same (proper or improper) rotation part and different translation parts. In other terms, isogonal isometries have the same matrix part but different vector parts. The term isogonal was also used to indicate space groups belonging to the same geometric crystal class.

### References

- Buerger, M.J. (1956).
*Elementary crystallography*. New York, Wiley.