TY - JOUR
T1 - The first binuclear sandwich-like complexes based on the aromatic tetraatomic species
AU - Wang, Congzhi
AU - Li, Nan
AU - Zhang, Xiuhui
AU - Ji, Lin
AU - Li, Qianshu
PY - 2011/7/14
Y1 - 2011/7/14
N2 - The first binuclear sandwich-like complexes based on the aromatic tetraatomic species with formula M2(η4-E 4)2 (M = Al, Ga; E = N, P, As) have been studied by density functional theory (DFT). The stable conformer for each M 2(η4-E4)2 is the staggered one with D4d symmetry except for Ga2(η2-N 4)2 with C2v symmetry. Natural bonding orbital (NBO) analysis indicates that the metal-metal bonds of Al2(η 4-E4)2 (E = N, P, As) and Ga 2(η4-E4)2 (E = P, As) are all σ single bonds, which are derived mostly from the s and pz orbitals of the metal atoms by molecular orbital (MO) analysis. For M 2(η4-E4)2 (M = Al, Ga; E = P, As), the metal-ligand interactions are covalent, while for Al 2(η4-N4)2 the interactions between the Al atoms and the N42- ligands are ionic. According to the calculated dissociation energies for breaking metal-metal bonds, the Al-Al and Ga-Ga bonds are very strong indicating that these stable sandwich-like compounds Al2(η4-E4) 2 (E = N, P, As) and Ga2(η4-E 4)2 (E = P, As) may be synthesized in future experiments. The nitrogen-rich compounds Al2(η4-N4) 2 and Ga2(η2-N4)2 may be used as potential candidates of high energy density materials (HEDMs). Nucleus-independent chemical shifts (NICS) values reveal that the E 42- rings in the Al2(η4-E 4)2 (E = N, P, As) and Ga2(η4- E4)2 (E = P, As) species possess conflicting aromaticity (σ antiaromaticity and π aromaticity) and with the same ligands, the E42- ligands in Ga2(η4-E 4)2 have more aromaticity than those in Al 2(η4-E4)2.
AB - The first binuclear sandwich-like complexes based on the aromatic tetraatomic species with formula M2(η4-E 4)2 (M = Al, Ga; E = N, P, As) have been studied by density functional theory (DFT). The stable conformer for each M 2(η4-E4)2 is the staggered one with D4d symmetry except for Ga2(η2-N 4)2 with C2v symmetry. Natural bonding orbital (NBO) analysis indicates that the metal-metal bonds of Al2(η 4-E4)2 (E = N, P, As) and Ga 2(η4-E4)2 (E = P, As) are all σ single bonds, which are derived mostly from the s and pz orbitals of the metal atoms by molecular orbital (MO) analysis. For M 2(η4-E4)2 (M = Al, Ga; E = P, As), the metal-ligand interactions are covalent, while for Al 2(η4-N4)2 the interactions between the Al atoms and the N42- ligands are ionic. According to the calculated dissociation energies for breaking metal-metal bonds, the Al-Al and Ga-Ga bonds are very strong indicating that these stable sandwich-like compounds Al2(η4-E4) 2 (E = N, P, As) and Ga2(η4-E 4)2 (E = P, As) may be synthesized in future experiments. The nitrogen-rich compounds Al2(η4-N4) 2 and Ga2(η2-N4)2 may be used as potential candidates of high energy density materials (HEDMs). Nucleus-independent chemical shifts (NICS) values reveal that the E 42- rings in the Al2(η4-E 4)2 (E = N, P, As) and Ga2(η4- E4)2 (E = P, As) species possess conflicting aromaticity (σ antiaromaticity and π aromaticity) and with the same ligands, the E42- ligands in Ga2(η4-E 4)2 have more aromaticity than those in Al 2(η4-E4)2.
UR - http://www.scopus.com/inward/record.url?scp=79959423046&partnerID=8YFLogxK
U2 - 10.1039/c1dt10508f
DO - 10.1039/c1dt10508f
M3 - Article
AN - SCOPUS:79959423046
SN - 1477-9226
VL - 40
SP - 6922
EP - 6928
JO - Dalton Transactions
JF - Dalton Transactions
IS - 26
ER -