Polychloride Monoanions from [Cl3]− to [Cl9]−: A Raman Spectroscopic and Quantum Chemical Investigation

Polychloride monoanions stabilized by quaternary ammonium salts are investigated using Raman spectroscopy and state‐of‐the‐art quantum‐chemical calculations. A regular V‐shaped pentachloride is characterized for the N(Me)₄]Cl₅] salt, whereas a hockey‐stick‐like structure is tentatively assigned for N(Et)₄]Cl₂???Cl₃^?]. Increasing the size of the cation to the quaternary ammonium salts NPr₄]⁺ and NBu₄]⁺ leads to the formation of the Cl₃]^? anion. The latter is found to be a pale yellow liquid at about 40 °C, whereas all the other compounds exist as powders. Further to these observations, the novel Cl₉]^? anion is characterized by low‐temperature Raman spectroscopy in conjunction with quantum‐chemical calculations.