book coordination chemistry Flashcards
d block metals are
lewis acids
they accept e- pairs
ligands are
lewis bases
they donate e- to the metal ion
ligands are usually
neutral (h2O, NH3)
an ionic (Cl-)
what do ligands do to the metal ion
they coordinate to the metal ion to give a complex
what is the donor atom in the ligand
the atom that supplies the e- pair
how do u name a coordinate ligand
normally add an ido to the halogens
water = aqua
ammonia = ammine
ligands with one donor atom are called
monodentate ligands
ligands with 2 donor atoms are called
bidentate ligands
what’s a polydentate ligand
a ligand that has more than 1 donor atom.
what’s a chelating ligand
a polydentate ligand
a ligand with more than 1 donor atom
what a chelate
a complex where it’s ligands are polydentate
how do we find the oxidation state of the metal in complex ions
outer charge - ligand charges
what is the coordination number of a complex
number of donor atoms that are bonded to the central metal ion.
coordination number of 2 gives whqt geometry
linear
•-•-•
coordination number of 3 gives what geometry
this complex is not very common
gives a trigonal planar shape.
coordination number of 4 gives what geometry
tetrahedral
square planar
coordination number of 5 gives what geometry
trigonal bipyramidal
square bipyramidal
(aside?)
complex with 6 ligands gives what geometry
octahedral
trigonal prismatic
complex with 7 ligands gives what geometry
pentagonal bipyramidal (5 equatorial, 2 axial )
capped trigonal prismatic
what is needed to get from trigonal prismatic to octahedral
turn the molecule 60*
what coordination number is most popular for the first row d block metals
octahedral
6
how can 2nd and 3rd row TM have higher coordination numbers
they have a higher ionic radii
name [Co(H2O)6]+2
hexaaquacobalt(||)
name [Ni(NH3)6]+2
hexaamminenickel(||)
what do u add to the name when the complex is anionic (has a - charge)
-ate is added to the metal
name [NiCl4] -2
tetrachloridonickelate (||)
how do we make different ligands in the same complex
write them alphabetically
in the formula, what type of ligands are written first
the anionic ligands
the - charged ligands
additional prefix due to already having a prefix for the other ligands present
bis - 2
tris - 3
tetrakis - 4
pentakis - 5
hexakis - 6
structural isomer
same empirical
diff connectivity
stereoisomer
same empirical
same connectivity
different arrangement of atoms in space
coordination chemistry structural isomer examples
ionisation
hydration
coordination
linkage
coordination complex stereoisomer examples
geometrical isomers
isomers with chiral centres
structural: ionisation isomers
different inner and outer sphere combinations
coordinated and non coordinated ligands switch.
what’s a counter ion
a ionic ligand that is not coordinated
structural isomers: hydrate ligands
different amounts of H2O in the inner and outer sphere
hydration isomers and their colours (chromium)
[Cr(h2o)6]cl3. -> violet crystals
[Cr(h2o)5 cl] cl2 • h2o -> blue/green
[Cr(h2o)4 cl2 ] cl • 2h2o -> dark green
[Cr(h2o)3 cl3 ] • 3h2o -> yellow
if smt is removed rapidly, what sphere must it be present in
the outer sphere
structural isomers: coordination isomers
when a coordination compound contains 2 complex ions.
they exchange ligands (swap metals over between the 2 complex ions)
structural isomers: linkage isomers
different donor atoms in an ambidentate ligand bond to the metal ion
use of kappa - k x
where x is the donor atom
what’s an ambidentate ligand
a monodentate ligand
with 2 donor atoms.
stereoisomers: geometric isomers
important in the use of the complex (cis platin - anti cancer)(trans platin- no use)
different spatial arrangement of ligands
meridional geometric isomerism
octahedral line
ligand lies on the meridian
facial geometric isomerism
octahedral triangle type shape
complexes can have a
enantiomer pair
- chiral compounds
- asymmetrical
- non superimposable mirror images of eachother
what’s an optical isomer
isomer with a chiral centre
tetrahedral complex enantiomers: the metal ligand bond is
labile- the ligands can break off and change places allowing the enantiomers to rapidly interconvert and undergo racemization
another type of chirality is seen in
octahedral geometries
chirality in octahedral geometry occurs with
bidentate ligands
what is the delta isomer
right handed clockwise helix
what is the lambda isomer /\
left handed
anti-clockwise helix
what enantiomers are possible to isolate
the delta and lambda enantiomers
they’re not labile
chelate vs ambidentate
chelate = claw,, can coordinate at 2 different areas at once
ambidentate: monodentate ligand but 2 diff possibilities
