What is a ligand
Neutral molecules or ions that have a lone pair that can be used to bond to a metal.
What is a metal?
Can accept more than one ligand
When a ligand bonds with a metal, what is it called if the result is an ion?
When a ligand bonds with a metal, what is it called if the result is a molecule?
What is more stable? When Ni ion complexes with NH3 or en?
When Ni complexes with en b/c same number of chemical species on both side of equation
What is coordination number?
Number of bonds formed by metal ions to ligands in complex ions
Results from interchange of anionic ligand in first coordination sphere with anion outside coordination sphere.
A type of stereoisomer where two molecules are non-superimposable mirror images of each other. Each mirror image is called an enantiomer.
Rules for naming complexes
- 1. Cation named first, then anion.
- 2. Names of anionic ligands always end in suffix -o
- a. ligands whose names end in -ide have
- suffix changed to -o
- b. ligands whose names end in ite or ate
- become ito and ato
- 3. neutral ligans give same name as used for molecule except aqua and ammine.
- 4. when ther is more than one of a given ligand, specify the number of ligands by prefixes di, tri, etc. for complex ligands bis, tris
- a. in formula, symbol of metal first followed by ligands with anionic ligands first in alphabetical order and neutral molecules second in alphabetical order.
- b. in the name of complex, ligands named first in alphabetical order and metal named last.
6. if complex ion has negative charge, the suffix ate is added to name of metal
7. sometimes latin name of metal is used.
8. oxidation number of metal is indicated in parentheses
What does crystal field theory attempt to explain?
Metal complexes color and magnetic properties.
What affects the crystal field splitting?
- 1. The nature of the ligand, some yield larger crystal field splittings, like CN, than other.
- 2. For a given metal and ligand, the size of cfs increases with an increase in the oxidation number of the metal
- 3. For a given ligand and oxidation state, the size of cfs increases going down a group
Why is Cr3+ more common than Cr2+
When you change Cr2+ to Cr3+ you lose a high energy electron (which is in an upper orbital) and cfs gets larger, so the electrons in the lower orbital have a lower energy
carbon produces greater cfs than nitrogen which produces greater cfs than oxygen than halides
What is pairing energy?
energy to force the electron into an orbital that's already occupied by an electron.
paramagnetic vs diamagnetic
- di - no unpaired electrons
- para- some unpaired electrons
High spin vs low spin
- High spin- highest number of paired electrons
- low spin - lowest number of paired electrons