https://www.selleckchem.com/pr....oducts/gsk3685032.ht
Three isomers of the allyl cation C3H5 + were obtained in salts with the carborane anion CHB11Cl11 -. Two of them, angular CH3-CH=CH+ (I) and linear CH3-C+=CH2 (II), were characterized by X-ray crystallography, and the third one, (CH2CHCH2)+ (III), is formed in an amorphous salt. The stretch vibration of the charged double bond C=C+ of I and II is decreased by 162 cm-1 (I) or 76 cm-1 (II) as compared to that of neutral propene. This result contradicts the prediction of DFT and MP2 calculations with the 6-311G++(d,p) basis set that th