TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Materials: (A) is supported on a porous substance. (A) forms a hydrogen molecular compound on contact with hydrogen gas (especially a hydrogen inclusion compound in which (A) is the host compound; more especially (A) is at least one from monomolecular, multimolecular and macromolecular host compounds). The monomolecular host compound is at least one from cyclodextrins, crown ethers, cryptands, cyclophanes, azacyclophanes, calixalens, cyclotriperatolylenes, spherands and cyclic oligopeptides. The multimolecular host compound is at least one from ureas, thioureas, deoxychols, perhydrotriphenylenes, tri-o-thymotides, vianthryls, spirobifluorenes, cyclophosphazenes, monoalcohols, diols, acetylene alcohols, hydroxybenzophenones, phenols, bisphenols, trisphenols, tetrakisphenols, polyphenols, naphthols, bisnaphthols, diphenylmethanols, carboxylic amides, thioamides, bixanthenes, carboxylic acids, imidazoles, hydroquinones, organophosphorous compounds and organosilicon compounds (especially at least one from 1,1-bis(4-hydroxyphenyl) cyclohexane, 1,1,2,2-tetrakis(4-hydroxyphenyl) ethane, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethylene, tetakis(p-methoxyphenyl) ethylene, 9,9'-vianthryl, 1,1,2,2-tetraphenylethane, diphenic bis(dicyclohexyl amide), fumaric bisdicyclohexylamide, alpha,alpha,alpha',alpha'-tetraphenyl-1,1'-biphenyl-2,2'-dimethanol, 1,1,6,6-tetraphenylhexa-2,4-diene-1,6-diol and 2-(m-cyanophenyl)phenanthro (9,10-d)imidazole). The macromolecular host compound is at least one from celluloses, starches, chitens, chitosans, polyvinylalcohols, 1,1,2,2-tetrakisphenylethane-core polyethylene glycolam type polymers and alpha,alpha,alpha',alpha'-tetrakisphenylxylene-core polyethylene glycolam type polymers. (A) is at least one from aromatic compounds (especially phenols), amides, alcohols, imidazoles, hydroquinones, ureas, carboxylic acids, cyclodextrins, polyphenols, cholic acids, celluloses and organophosphorous compounds.Preferred Method: The pressure is at least 1.0x10-10 (especially 1.0x10-10-200) MPa.Preferred Inclusion Compound: The host compound is at least one from the above monomolecular, multimolecular and macromolecular host compounds and inorganic host compounds (especially the inorganic host compound is at least one from clay minerals, montmorillonites and zeolites). EXAMPLE - 0.6502 g 1,1-bis(4-hydroxyphenyl)cyclohexane powder was charged in a test tube, heated at 50degreesC, vacuum pumped 3 h, hydrogen gas introduced at 25degreesC with increasing, then decreasing pressures, and the amount of included hydrogen measured at each pressure. The included gas was 2.72E-5 wt.% at 0.285 MPa, 4.69E-2 wt.% at 4.74 MPa, and then 7.3E-2 wt.% at 0.858 MPa and 6.83E-2 wt.% at 0.315 MPa. The gas was discharged by heating at 50degreesC under normal and 0.005 MPa pressures.