The purpose of this work is to introduce and study the notion of
spherical-vectors, which we can consider as a natural generalization of the
arguments of complex numbers in the case of quaternions. After having
established some elementary properties of these particular vectors, we show by
transport of structure that spherical-vectors form a non-abelian additive
group, isomorphic to the group of unit quaternions. This identification allows
us, first, to present a new polar form of quaternions, then to represent the
unit quaternions on the unit sphere of R3 and to interpret their
multiplications geometrically.Comment: 20 pages, 9 figure