Quintuple bond

A quintuple binding is a type of chemical bond between two atoms, which is conveyed via pairs of electrons ( electron pair binding). Between the atoms provide five pairs of bonding electrons the cohesion of the building upon the molecule.

The only in November 2005 by Philip Power et al. discovered quintuple bond consists of a metal -metal bond of the compound Ar - Cr2 -Ar (dark red crystals, thermally stable up to 200 ° C) with an aryl group ( Ar = terphenyl ligand C6H3 -2, 6 - ( C6H3 -2, 6- IPR2 ) 2).

The binding is made up of the following individual commitments:

• A σ - bond ( dz2 )
• Two π - bonds (each degenerate, a nodal plane dxz, dyz )
• Two δ bonds (each degenerate, two nodal planes, dxy and dx2 - y2)

Thus, the quintuple bond differs only by an additional ( degenerate ) δ bond of the quadruple bond.

Meanwhile, pentavalent compounds based on N -donor ligands are known in addition.