Infinity symbol in bookbinding to indicate that a book is printed on acid-free paper and will therefore be long-lasting. In modern mysticism, the infinity symbol has become identified with a variation of the ouroboros, an ancient image of a snake eating its own tail that has also come to symbolize the infinite, and the ouroboros is sometimes drawn in figure-eight form to reflect this identification, rather than in its more traditional circular form. In the works of Vladimir Nabokov, including "The Gift" and "Pale Fire", the figure-eight shape is used symbolically to refer to the Möbius strip and the infinite, for instance
Polyhedral symbol the lowest numerical sequence is chosen. Polyhedral symbol The polyhedral symbol is sometimes used in coordination chemistry to indicate the approximate geometry of the coordinating atoms around the central atom. One or more italicised letters indicate the geometry, e.g. "TP"-3 which is followed by a number that gives the coordination number of the central atom. The polyhedral symbol can be used in naming of compounds, in which case it is followed by the configuration index. The first step in determining the configuration index is to assign a priority number to each coordinating ligand according to the Cahn-Ingold-Prelog priority rules, (CIP