TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preparation: No preparation method is given.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The thermoelectric material has: a two-dimensional layered structure; an one-dimensional or two-dimensional lattice distortion in an in-plane direction and a disordered layered structure in an alpha -axis direction that is perpendicular to the in-plain direction; a thermal conductivity of less than or equal to 2 W/mK at room temperature; a degree of crystallinity that is a rate of a crystal domain having the same crystal face in the range of 10-100%. In the thermoelectric material, a covalent bond is formed in an in-plane direction, and an ionic bond and/or Van der Waals bond is formed between layers. The thermoelectric device further comprises an insulating substrate on which one of the first electrode and the second electrode is disposed, where one of the first electrode and the second electrode is configured to be exposed to a heat source, or coupled to a power source. Preferred Definitions:    A1 = Ga and/or In;    B1 = S, Se and/or Te;    a, b, x, y = 0-0.5; and    z = greater than 0 and less than 0.1.    SPECIFIC COMPOUNDS - 5 Compounds (I) are disclosed e.g. metal compounds of formulae (In(4)Se(2.67)Cl(0.03)) (Ia), (In(4)Se(2.32)Cl(0.03)) (Ib), (In(4)Se(2.32)F(0.03)) (Ic), (In(4)Se(2.32)Br(0.03)) (Id) and (In(4)Se(2.32)I(0.03)) (Ie).    EXAMPLE - Selenium and indium(III) chloride were quantified to meet a corresponding stoichiometric molar ratio and added to a quartz tube. The quartz tube was sealed in a vacuum using a hydrogen torch and heat treated at 500 degrees C for 24 hours. A melt ingot was pulverized to prepare a metal powder, and the metal powder was compressed at 3 tons in a cold press mold. The resultant was sintered at 520 degrees C for 24 hours. The resultant was further pulverized to obtain a metal powder to have uniformity and sufficient density. The metal powder was compressed at 70 MPa at 480-500 degrees C for 1 hour to obtain corresponding chalcogenide (indium(4)selenium(2.67)chlorine(0.03)).