How do fac and mer isomers differ?
When three identical ligands occupy one face, the isomer is said to be facial, or fac. If the three ligands and the metal ion are in one plane, the isomer is said to be meridional, or mer.
What is fac and mer isomers?
Fac/Mer isomers arise when there are two equal types of ligand in an octahedral metal complex. • Fac – When one type of ligand occupies. one face of the octahedron. • Mer – Each set of identical ligands. occupy a plane of the octahedron (2 of the same ligands are trans to each other, the other ligand is cis to these.)
Is FAC or MER more stable?
A negative value indicates that the mer isomer has a lower energy than the fac, i.e. the mer isomer is more stable.
Is octahedral symmetrical?
In chemistry, octahedral molecular geometry describes the shape of compounds with six atoms or groups of atoms or ligands symmetrically arranged around a central atom, defining the vertices of an octahedron. The octahedron has eight faces, hence the prefix octa.
Is FAC and Mer geometric isomers?
Geometric Isomers are isomers that differ in the arrangement of the ligands around the metal or the central atom. There are 2 main types of geometric isomers: Cis-Trans Isomers (referencing the spatial arrangement of two species) Mer-Fac Isomers (referencing the spatial arrangement of three species)
Are fac and mer isomers optically active?
The facial and meridional isomers of an MA3B3 octahedral complex are both optically active. In an octahedral complex 1,2 positions are cis positions as they have 90∘ separation While 1, 6 positions are trans positions as they have a 180∘ separation.
Is fac isomer optically active?
But the fac-isomer has no plane of symmetry. Still, it is optically inactive, why?
How many symmetries does a dodecahedron have?
The most familiar dodecahedron is the regular dodecahedron with regular pentagons as faces, which is a Platonic solid. There are also three regular star dodecahedra, which are constructed as stellations of the convex form. All of these have icosahedral symmetry, order 120….
| Pyritohedron | |
|---|---|
| Properties | face transitive |
| Net |
How are fac Mer isomers calculated?
Another way to identify fac isomers is to look at the bond angle between the ligands because fac isomers have a 90o bond angle between each of the 3 atoms. The mer isomer on the other hand is where only 2 of the 3 ligands are on the same side.
Why fac and mer isomers are optically inactive?
If we look closely at the mer-isomer, it has a plane of symmetry, so it is optically inactive. But the fac-isomer has no plane of symmetry.
CAN CO nh3 3cl3 show optical isomerism?
[Co(NH3)3Cl3] four geometric isomers are possible. All the four geometric isomers are un-symmetrical and each shows optical isomerism i.e., forms two optical isomers d and l forms which are mirror image of each other in similar way as shown in (a).
