Insights on the structural and electronic properties of ScC n + , YC n + , LaC n + (n = 3–6) systems

The nature of the chemical bonds in the EC3+, EC4+, EC5+, and EC6+ species (E = Sc, Y and La) has been examined in depth using a combination of different theoretical strategies. Firstly, exhaustive explorations of the relevant potential energy surfaces using a combination of stochastic and gradient-based search procedures provide us with fan-like structures in singlet and triplet spin states as the most energetically stable configurations. Secondly, the chemical bonding analysis, using natural bond orbital theory, energy decomposition analysis, quantum theory of atoms in molecules, and the adaptive natural density partitioning analysis, indicate that metal–carbon interaction in these species is best described as an intermediate point between ionic and covalent.