On properties of interpolation groups

Partially ordered groups satisfying the interpolation condition (and not necessarily directed) are considered. It is proved that an isomorphism theorem holds for these groups (this theorem fails to hold for partially ordered groups in the general case). A criterion for almost orthogonality of positive elements of interpolation groups is found. The location of a subgroup associated with a pair of almost orthogonal elements in the lattice of subgroups of an interpolation group is described.