[en] The geometric, energetic, spectral and electronic properties of various isomers of B₁₂H_C...(NF₂)_12-C... ²⁻ anion complex with x = 9 − 12 have been studied using Density Functional Theory (B3LYP/6-311++G**). It was shown that the most stable isomers are characterized by the preference to form the most symmetric structures with uniformly distributed charge densities. However, when replacing a hydrogen atom with difluoramino group, an inductive effect occurs. NF₂ group pulls a part of electron density that leads to the polarization of the boron core. Blue shifts in the IR spectrum compared to the vibrations of the free radical NF₂ ranging from 5 to 69 cm⁻¹ for the most stable isomers with the minimum total energy are characteristic and points to the stability of B₁₂H_C...(NF₂)_12-C... ²⁻ anions. The obtained results broaden the idea of aromaticity of B₁₂H₁₂ ²⁻ anion and will be useful in synthesis of new B₁₂H₁₂ ²⁻ derivatives. (paper)