The present invention provides a porous coordination polymer, wherein the porous coordination polymer is formed of unit lattices; each of the unit lattices has a shape of a cube having eight vertexes and twelve sides; each of the vertexes of the unit lattices consists of a Zn.sub.4O cluster; each of the sides of the unit lattices consists of a .sup.−OOC—C≡C—COO.sup.− group. At least a part of the unit lattices contains at least one hydrogen molecule only, or the inside of at least a part of the unit lattices is empty. The present invention provides a novel porous coordination polymer, especially, a porous coordination polymer suitable for separating hydrogen molecules from a gaseous mixture of the hydrogen molecules and impurity molecules (e.g., nitrogen molecules, oxygen molecules, or carbon dioxide molecules).

The present invention provides a porous coordination polymer, wherein the porous coordination polymer is formed of unit lattices; each of the unit lattices has a shape of a cube having eight vertexes and twelve sides; each of the vertexes of the unit lattices consists of a Zn.sub.4O cluster; each of the sides of the unit lattices consists of a .sup.OOCCCCOO.sup. group. At least a part of the unit lattices contains at least one hydrogen molecule only, or the inside of at least a part of the unit lattices is empty. The present invention provides a novel porous coordination polymer, especially, a porous coordination polymer suitable for separating hydrogen molecules from a gaseous mixture of the hydrogen molecules and impurity molecules (e.g., nitrogen molecules, oxygen molecules, or carbon dioxide molecules).