Effect of the structure of the π-ligand on the mechanism of ion-molecule reactions in the (η6-ARENE) chromium tricarbonyl-ammonia system

Double aromaticity in transition metal centered double-ring boron clusters M@B2n (M = Ti, Cr, Fe, Ni, Zn; n = 6, 7, 8)

“…Fe@B 16 has the similar electronic structure with Ni@B 14 due to the same number of delocalized electrons . The CMO results plotted in Figure 3 reveal that there are three delocalized π orbitals with six valence electrons in tangential direction and nine spd-π delocalized orbitals (S, P x,y,z , and D xy,yz,xz,x2-y2,z2 ) with 18 electrons in radial direction.…”

“…All these calculations are carried out on the TPSSh/ 6-31G*/LANL2DZ level. From the results of the electronic structures analysis, we suppose that all the five stable compounds (Ni@B 12 , Cr@B 14 , Ni@B 14 , Cr@B 16 , and Fe@B 16 ) could be classified into three categories.…”

“…As a result, although Cr@B 14 has only seven delocalized spd-π orbitals with 14 electrons in radial direction, it also keeps stability due to its special structural shape. Category III includes Ni@B 12 and Cr@B 16 . For Ni@B 12 , three delocalized π orbitals in the tangential direction and eight delocalized orbitals in the radial direction are obtained in Figure 5(a) by CMO analysis.…”

“…For the relative less stable compounds of Fe@B 14 and Ni@B 16 , the CMO analyses are also used to identify their electronic structures. It is found that Fe@B 14 has got three delocalized π orbitals in the tangential direction and eight delocalized spd-π orbitals in the radial direction (Figure 7(a)).…”

“…At first, metallocenes with organic ligands held most of the interests of researchers. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] However, the reports on the inorganic ligands, which were found have the similar delocalized bondings, had grown rapidly since the beginning of 21st century. In recent years, all-boron clusters were considered as potential new inorganic ligands because of their aromatic and antiaromatic electronic properties similar to the hydrocarbons.…”