Download 1.1 Werner`s Coordination Theory 1.2 Coordination

Chapter 2
Chapter 2
1.1 Werner’s Coordination Theory
1.2 Coordination Geometries
 Oxidation state
 Possible geometries with coordination number = 6
1
 Coordination number
M
2
3
5
4
1
4
6
2
M
3
5
M
6
3
2
M
2
4
5
6
Chapter 2
3
1
1
5
5
6
6
2
M
M
3
4
 Isomer
6
4
2
5
1
1
3
4
Chapter 2
1.3 Isomers for MA4B2
A
A
A
A
M
A
A
B
B
A
M
A
A
B
A
A
B
B
B
B
M
A
M
B
A
A
1.4 Isomers for Co(NH3)4Cl2
A
A
A
B
A
M
A
A
A
M
A
B
A
B
B
A
B
B
B
A
M
A
A
A
M
A
A
A
A
B
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Chapter 2
Chapter 2
2.1 Writing Modern Formulas
 Examples
2.2 Ligands
 Ligands – molecules or ions (Lewis bases) that bind
to the metal by sharing (donating) a pair of electrons
 Denticity – number of pairs of electrons donated by a
particular ligand
 Chelate – ligand that binds to a metal through more
th one pair
than
i off electrons
l t
 Bridging ligands – ligands that donate electron pairs
to more than one metal
Chapter 2
Chapter 2
2.3 Common Ligands
 Common monodentate ligands
2.4 Common Ligands
 Common bridging ligands
2
Chapter 2
Chapter 2
2.5 Common Ligands
 Ambidentate ligands
Chapter 2
2.6 Common Ligands
 Common multidentate (chelating) ligands
Chapter 2
2.7 Writing Modern Formulas
 A Ni2+ is bound to two H2O and two oxalate ligands,
with two NH4+ counterions
 A Co3+ is bound to one chloride, one NH3, and two
ethylenediamine ligands, with a SO42- counterion
 A Cr3+ is bound to two phenanthroline and two nitrite
ligands
 What’s the charge on the complex?
2.8 Writing Formulas
 A compound with composition CuCl2  4NH3 is
comprised of a Cu2+ ion and has an overall metal
complex charge of 2+
2
 What’s the coordination number of Cu?
 What’s the modern formula?
 A complex consists of a Mo ion bound by three CO and
three thiocyanate ligands. If the overall charge on the
metal complex is 1+, what’s the oxidation state of Mo?
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Chapter 2
Chapter 2
3.1 Nomenclature
1.
3.2 Nomenclature
If the compound is ionic, name the cation portion first
2.
When naming the metal complex, first name the ligands, in
alphabetical order, followed
f
by the name off the metal
a. If ligand is an anion whose name ends in –ite or –ate, the
final “e” is change to an “o”
 Sulfate  sulfato; nitrite  nitrito
b. If ligand is an anion whose name ends in –ide, the ending is
changed to “o”
y
 cyano
y
 Chloride  chloro;; cyanide
c. If ligand is neutral the common name is used
 Exceptions include water (aqua), ammonia (ammine),
carbon monoxide (carbonyl)
d.
e.
3.
4.
Chapter 2
If there is more than one of a particular monodentate ligand,
the number of ligands is indicated by a prefix (di, tri, tetra,
penta, hexa)
If the ligand name is more complicated or already contains
numerical prefixes (such as di, tri), the ligand prefix becomes
bis, tris, tetrakis, with the ligand name in parentheses
If the metal complex is an anion, the suffix –ate is added to the
metal name
a. If necessary, drop -ium, -en, -ese ending before adding –ate
b. “cobaltate”, “nickelate”, “chromate” (not chromiumate),
“manganate” (not manganeseate)
c. What if the metal is iron, gold, or copper?
Following the metal’s name, its oxidation state is given by a
Roman numeral in parentheses
Chapter 2
3.3 Nomenclature

Examples
 [Cu(NH3)4]SO4 = tetraamminecopper(II) sulfate
 K2[CoCl4] = potassium tetrachlorocobaltate(II)
 Co(phen)2Cl2 = dichlorobis(phenanthroline)cobalt(II)
 [Co(en)2(H2O)Cl](NO3)2 =
aquachlorobis(ethylenediamine)cobalt(III) nitrate
 Name the compounds:
 [[Ru(en)
( )2((H2O)SCN]Cl
)
]
3.4 Nomenclature

Name the compounds:
 [Mo(ox)2(H2O)SCN]NO3
 K4[Cr(CN)4Br2] (both isomers)
 Fe(CO)3(py)2
 Pt(NH3)2Cl2
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Chapter 2
3.5 Nomenclature

Deduce the formula from the name:

potassium tetracyanonickelate(II)

amminebis(ethylenediamine)thiocyanatocobalt(III) nitrate

tetraaquadihydroxomanganese(III) bromide

tetrakis(pyridine)platinum(II) tetrachlorocuprate(II)
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