Coordination complexes Flashcards
(20 cards)
What are coordination numbers in transition metal complexes?
Transition metal ions usually form complexes with a well-defined number of ligands, primarily four and six.
Coordination numbers two and five are also established.
What shapes do four-coordinate transition metal ions adopt?
Tetrahedral or square planar coordination. (SP almost always d8 orbitals)
Examples include FeCl2− (tetrahedral) and AuCl− (square planar).
What is the common shape of six-coordinate species?
Nearly always octahedral.
What are the possible shapes of five-coordinate species?
Trigonal bipyramidal or square base pyramidal.
An example of square base pyramidal is VO(acac)2.
What is the limitation of using hybridisation for transition metal complexes?
Hybridisation is generally found not to be satisfactory for explaining bonding in transition metal complexes.
What hybridisation is associated with the carbon in CH4?
sp3 hybridised.
What hybridisation is associated with the carbon in C2H4?
sp2 hybridised.
What hybridisation is associated with the carbon in C2H2?
sp hybridised.
What is the hybridisation for an octahedral complex?
sp3d2 hybridisation.
What is the electronic configuration of Sc2+?
3d14s2.
What is the electronic configuration of Ti2+?
3d24s2.
What is the electronic configuration of Fe2+?
3d64s2.
In an octahedral complex, which orbitals are used for bonding?
4s, 4px, 4py, 4pz, 3dz2, 3dx2−y2.
What is the electronic configuration of Ti3+ in [Ti(H2O)6]3+?
3d14s0.
What does the splitting diagram of Co3+ (d6) show in [Co(NH3)6]3+?
Diamagnetic with no unpaired electrons.
What is the outcome of the hybridisation model for [Co(CN)6]4− (d7)?
It cannot be explained by hybridisation (valence bond theory).
What is the common hybridisation found in tetrahedral complexes?
Hybridisation works for tetrahedral complexes.
What key concepts have been covered in this study guide?
Stereochemistry, bonding, and limitations of hybridisation in transition metal complexes.
True or False: Square planar complexes nearly always involve d8 metals.
True.
Fill in the blank: Coordination numbers _____ and _____ are the most common in transition metal complexes.
four, six.
