Hexaaquanickel diorotate(1-) dihydrate at 150 K

Area of Science:

• Crystal chemistry
• Coordination chemistry
• Supramolecular chemistry

Background:

• Orotate is a pyrimidine derivative involved in various biological processes.
• Nickel complexes exhibit diverse coordination geometries and properties.
• Hydrogen bonding plays a crucial role in crystal engineering and molecular self-assembly.

Purpose of the Study:

• To elucidate the crystal structure of hexaaquanickel bis(orotate) dihydrate.
• To investigate the coordination environment of the nickel ion.
• To understand the intermolecular interactions governing the crystal packing.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
• Analysis of bond lengths, bond angles, and hydrogen bonding networks was performed.
• Comparison with isotypic magnesium and zinc analogues was conducted.

Main Results:

• The nickel cation is octahedrally coordinated by six water molecules, forming a hexaaquanickel(II) complex.
• Orotate anions are linked to the hexaaquanickel complex via hydrogen bonds, not direct coordination.
• Orotate moieties form one-dimensional chains through self-recognition hydrogen bonding.
• Hexaaquanickel complexes act as molecular clamps, bridging these chains and forming a 3D network.
• A short intermolecular carbon-carbon contact of 3.166 Å was observed between adjacent ribbons.

Conclusions:

• The crystal structure of hexaaquanickel bis(orotate) dihydrate is characterized by a unique 3D arrangement driven by hydrogen bonding.
• The complex exhibits an isotypic structure with its magnesium and zinc counterparts.
• The observed short carbon-carbon contact suggests potential for further structural modifications and applications.