Final answer:
Decacarbonyldimanganese has two Mn atoms with different molecular geometries: trigonal bipyramidal and octahedral, not square pyramidal. The structure involves low oxidation states of manganese and each Mn atom is surrounded by CO ligands in varying geometries.
Step-by-step explanation:
The structure of decacarbonyldimanganese (Mn2(CO)10), which is often referred to as decacarbonyl manganese, is not square pyramidal. Instead, the correct molecular geometry for this compound is trigonal bipyramidal for the central Mn atom that is bonded to five CO ligands and octahedral for the central Mn atom bonded to the other five CO ligands. In Mn2(CO)10, there are two Mn atoms each with a different molecular geometry due to the bridging CO ligands. One Mn forms a trigonal bipyramid with three equatorial and two axial CO ligands, while the other Mn atom forms an octahedral geometry with its six CO ligands.
Decacarbonyldimanganese is a complex where low oxidation states of manganese are observed, specifically Mn in the oxidation state of +1. The term square pyramidal can describe a molecular geometry based on an octahedral structure where one position (vertex) is unoccupied. However, this is not applicable to Mn2(CO)10.