TECHNOLOGY FOCUS - ELECTRONICS - Preferred Component: The buffer layer is formed as a thin film using a spin coating method, a dip coating method, a roll coating method, a screen coating method, a spray coating method, a spin casting method, a flow coating method, a screen printing method, an ink jet method, a drop casting method, or a vacuum deposition method. The electronic device can be an organic thin film transistor comprising a substrate, a gate electrode, a gate insulation layer, a source electrode, a drain electrode, the buffer layer formed on the source/drain electrode, and an organic semiconductor layer. Preferred Property: A thickness of the buffer layer is 0.1-100 nm.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Disclosed): The metal complex (1) may be prepared by mixing a solution, in which a compound containing a nitrogen atom having an unshared electron pair in a ring may be dissolved in a solvent, with a solution, in which a metal salt (e.g., metal halide, particularly metal chloride) may be dissolved in a solvent at room temperature, or at less than or equal to 50 degrees C. Preferred Component: A substitution group (with which the aryl or heteroaryl is substituted) is one or more of a linear or branched 1-10C alkyl, a perfluoroalkyl, a halogen, a hydroxy, a nitro, an amino, a cyano, an alkoxy, an amidino, or a carboxyl. Preferred Compounds: The metal complex (1) is represented by formula (3). The metal complex (3) is represented by formula (4), (5) or (6).R3-R6=linear or branched 1-10C alkyl, perfluoroalkyl, H, halo, OH, NO2, NH2, CN, alkoxy, amidino, or carboxyl. Preferred Definitions:    X=one or more of 10 heteroaromatic organic groups, e.g. formula (2); and    R1, R2=optionally substituted 6-30C aryl, or optionally substituted 2-30C heteroaryl.    EXAMPLE - A solution (1 mM), in which 10 mg of a prepared Flu-SPNB-Flu of formula (9) may be dissolved in 10 ml chlorobenzene, was mixed with a solution (0.1 mM), in which 0.2 mg chloroauric acid (HAuCl4) (oxidant) was dissolved in 10 ml chlorobenzene at 5 degrees C. As a result, a Flu-SPNB-Flu-Au solution of formula (4) was prepared.