Polychloride Monoanions from [Cl 3 ] − to [Cl 9 ] − : 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 ][Cl 5 ] salt, whereas a hockey‐stick‐like structure is tentatively assigned for [N(Et) 4 ][Cl 2 ⋅⋅⋅Cl 3 − ]. Increasing the size of the cation to the quaternary ammonium salts [NPr 4 ] + and [NBu 4 ] + leads to the formation of the [Cl 3 ] − 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 [Cl 9 ] − anion is characterized by low‐temperature Raman spectroscopy in conjunction with quantum‐chemical calculations.