TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Solar Cell: A solar cell has sequential lamination of transparent conductive layer, electric power generation layer containing the metal complex and oxide semiconductor, and electrode layer.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): The compound containing group 10 element or metal of group 10 element and 4,4'-bipyridyl derivative of formula (2) are reacted, to obtain the metal complex of formula (1).Preferred Complex: The metal complex has the structure of formula (3).R = H or halogen atom;M = same as defined above;andbroken line = coordinate bond.Preferred Method: The compound containing group 10 element and 4,4'-bipyridyl derivative of formula (2) are reacted in presence of a reducible compound.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: A polymer composition for film, contains the metal complex and gas barrier materials. Preferred Definitions:    (C5R4N)2 = 4,4'-bipyridyl derivative of formula (2), preferably 4,4'-bipyridyl;and    R = same as defined above.    EXAMPLE - Tris(dibenzylideneacetone)dipalladium (in mg) (385.7), 4,4'-bipyridyl (263.1), tetrahydrofuran (12.5 ml) and acetone (25 ml), were mixed in presence of nitrogen for 1 hour and heated at 60degreesC for 60 hours. The obtained solid was filter-separated, washed and dried to obtain red colored metal complex having palladium coordinated to nitrogen of 4,4'-bipyridyl, at a yield rate of 61%. The compound was stable even in air. The obtained palladium complex (200) was mixed with Panlite (RTM: polycarbonate having glass transition point of 149degreesC) (10 g) and methylene chloride (50 ml), at room temperature for 1 hour. The obtained mixture was flow-spread on a glass plate, dried and peeled to form a film of 50 microns thickness. The oxygen permeability of the film measured at 23degreesC and 50% relative humidity was less than 1.9 ml/m2/day/Pa. The water vapor permeability of the film after preservation in thermo hygrostat at 45degreesC and 90% relative humidity for 100 hours was 5.3 g/m2/day.