In the solid state the coordination sphere for niobium is a distorted octahedron.

In this way, the compound is best described as a polymer, consisting of a double stranded chain.

[1][2] In the gas phase above 320 °C the Raman spectrum is consistent with a pyramidal monomer containing a niobium–oxygen double bond.

[3] Niobium oxychloride is prepared by treating the pentachloride with oxygen:[4] This reaction is conducted at about 200 °C.

NbOCl3 also forms as a major side-product in the reaction of niobium pentoxide with various chlorinating agents such as carbon tetrachloride and thionyl chloride.