CH42+ dication

Such high rotationally excited states in diatomic systems play a significant role in understanding molecular processes occurring in interstellar space [49]. For the specific system of H2+, these rotationally hot states can be produced for instance by the dissociation of CH42+ dications [50]. 

Varied Methane Cations. The methane molecular ion (methane radical cation, CH4+ ), the parent ion in mass spectrometry, and the methane dication (CH42+) are of great significance and have been studied both experimentally and theoretically.800 802 Recent advanced studies have shown that the methane radical cation, CH4+ has a fivecoordinate planar structure as suggested in early calculations by Olah and Klopman.800... 

The methane dication (CH42+) with a lifetime of only 3 jxs803 has been detected experimentally in the gas phase.804-807 A square-planar D4h symmetrical structure was predicted by early calculations.808,809 However, the planar but not square C2v symmetrical form (443) was shown to be the preferred structure by Wong and Radom.810 The cation contains an, vp2-hybridized carbon, an empty p-orbital perpendicular to the plane of the molecule, and a 2e-3c interaction. It can be visualized as a complex of a hydrogen molecule weakly bounded by a 2e-3c bond to the CH22+ core as shown by ab initio calculations [MP2 and B3LYP levels with 6-311++G(2df,2pd) basis set].811 The pentacoordinate CH52+ radical dication was studied by Stahl... 

Varied one carbon geminal dications have been generated in the gas-phase and studied by theoretical methods. For example, mass spectroscopic studies of methane have detected dicationic species, CH42+, CH3 2+, CH22+, and CH 2+, while other studies have examined the structures of halogenated one carbon geminal dications.13 The halogenated systems... 

---