NOVELTY - The thermoelectric material is based on the skutterudite structure with heavy filling atoms in the empty octants, with substitution of transition metals and main-group atoms. Metal atoms (202) form a cubic lattice (204) which has eight octants. Six octants are each occupied with a square planar ring (208) formed by four non-metal atoms (206). Two filling atoms (210) fill the remaining two empty octants. This enables the skutterudite structure lattice to be represented by a 34 atom unit cell with eight metal atoms, twenty-four non-metal atoms and two filling atoms.    USE - For thermoelectric devices such as thermoelectric power generators used in space craft during deep space missions, for use in heat recovery from processing plant of combustible solid waste, or for generating electric power from waste exhaust heat, e.g. to supplement or replace the alternator in motor vehicles. Can also be used thermoelectric refrigeration and cooling applications, heating applications and sensing applications.    ADVANTAGE - High Seebeck coefficients and low thermal conductivities are achieved in combination with large electrical conductivities in these filled skutterudites for large ZT values    DETAILED DESCRIPTION - The material includes:    (i) a first component of a first amount from a first non-metal element from the fourteenth, fifteenth, and sixteenth columns of the periodic table including pnicogen elements and chalcogen elements;    (ii) a second component of a second amount from a first transition metal element; the first component of the first pnicogen element and the second component of the first transition metal element positioned relative to each other to form a skutterudite structure having a formula: T4 Pn12,    where T represents the first transition metal element and Pn represents the first non-metal element;    (iii) a third component of a third amount from a first metallic element including a first rare-earth element;    (iv) a fourth component of a fourth amount from a second non-metal element selected from the fourteenth, fifteenth, and sixteenth columns of the periodic table, substituting a first portion of the first non-metal element while maintaining a total amount of the first non-metal element and the second non-metal element at the first amount;    (v) a fifth component of a fifth amount from a second transition metal element, substituting a second portion of the first transition metal element while maintaining a total amount of the first transition metal and the second transition metal element at the second amount; and    (vi) a sixth component of a sixth amount from a second metallic element including a second rare-earth element. The first, second, third, fourth, fifth and sixth components form the hybrid material with a nominal composition represented by a formula:    Rf(1-r) Rfr T4-x Tx Pn12-y Pny, for    0 at most f at most 1, 0 at most r at most 1, 0 at most x at most 4, and 0 at most y at most 12    where T, Pn, R, and R respectively represent the second transition metal element, the second non-metal element, the first metallic element and the second metallic element; and the first, second and third amounts being proportional relative to each other so that the hybrid material has transport properties of being semimetallic or semiconducting.    An INDEPENDENT CLAIM is included for a method of fabricating a thermoelectric alloy of a filled skutterudite structure.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of a filled skutterudite structure, including eight transition metal atoms, twenty-four pnicogen atoms and two filling atoms.    metal atoms (202)    cubic lattice (204)    non-metal atoms (206)    square planar ring (208)    filling atoms (210)