Point Groups in Three Dimensions - Relation Between Orbifold Notation and Order

Relation Between Orbifold Notation and Order

The order of each group is 2 divided by the orbifold Euler characteristic; the latter is 2 minus the sum of the feature values, assigned as follows:

  • n without or before * counts as (n−1)/n
  • n after * counts as (n−1)/(2n)
  • * and x count as 1

This can also be applied for wallpaper groups and frieze groups: for them, the sum of the feature values is 2, giving an infinite order; see orbifold Euler characteristic for wallpaper groups

Read more about this topic:  Point Groups In Three Dimensions

Famous quotes containing the words relation and/or order:

    You see, I am alive, I am alive
    I stand in good relation to the earth
    I stand in good relation to the gods
    I stand in good relation to all that is beautiful
    I stand in good relation to the daughter of Tsen-tainte
    You see, I am alive, I am alive
    N. Scott Momaday (b. 1934)

    I have been in the editorial business going on fourteen years, and it is the first time I ever heard of a man’s having to know anything in order to edit a newspaper.
    Mark Twain [Samuel Langhorne Clemens] (1835–1910)