[{"from": "human", "value": "Create a molecule with the structure as the one described. The molecule is a hard, high-melting (refractory) high-density dark gray metal or black powder. Insoluble in water. Used to make structural alloys; used as a catalyst. Molybdenum dust and fumes can irritate the eyes and respiratory tract."}, {"from": "gpt", "value": "[Mo]"}]