The present invention provides electrically and thermally conductive compositions for forming interconnections between electronic elements. Invention compositions comprise three or more metal or metal alloy particle types and an organic vehicle comprising a flux that is application specific. The first particle type includes a reactive high melting point metal that reacts with a reactive low melting point metal(s) in the other particles to form intermetallic species. The reactive low melting point metal(s) of the invention are provided in two distinct particle forms. The first reactive low melting point metal particle includes a carrier that facilitates the reaction with the reactive high melting point metal. The second reactive low melting point metal particle acts primarily as a source of the reactive low melting point metal. Combination of the three particle types provides several advantages including reduction of the undesirable characteristics of the carrier metal while preserving and, in some embodiments, enhancing, the advantageous facilitation of the metallic reaction.