Transcript CHEM 232 Inorganic Chemistry II (Spring 2004)

CHEM 232 Inorganic Chemistry II
(Spring 2006)
 Instructor: Wa-Hung Leung (ext. 7360, [email protected])
Office: Rm 4528 (Lift 25/26), Lab: Rm 7141
 TAs: (1) Zhang Li ([email protected])
(2) Yi Xiaoyi ([email protected])
(3) Wong Wang Yee ([email protected])
(4) Au Yeung Siu Fung ([email protected])
 Class schedule:
Lecture: Mon/Wed/Fri, 13:00-13:50 (Rm 2464)
Tutorial/example class (4) : To be confirmed
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Course Contents
1.
2.
3.
Coordination Chemistry
Crystal field theory
Spectral, magnetic, thermochemcial properties
Coordination equilibria, chelate effect
Organometallic chemistry
18 e rule,
Carbonyl, olefin, cycloolefin compounds,
Organometallic reactions, homogeneous catalysis
Main group chemistry
Hydride and alkyl compounds
Element-element multiple bonds
Inorganic rings and cages
Silicates and aluminosilicates
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Assessment scheme
Attendance of lectures and
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Quizzes (4)
Assignments (2)
Mid-term exam (~ week 8/9)
Final exam
Tutorials (4) and others
8%
2x4%
38%
40%
6%
• Check out a PRS handset!
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Textbooks and references books
Textbook:
 “Inorganic Chemistry” by C. E. Housecroft and A. G. Sharpe,
Prentice Hall (1st ed., 2001; 2nd ed., 2005)
Other suggested readings:
 Inorganic Chemistry, 3rd ed., by D. F. Shriver et al., OUP (1999).
 Basic Inorganic Chemistry, 3rd ed., by F. A. Cotton et al., Wiley
(1995)
 Concepts and Models of Inorganic Chemistry, 3rd ed., by B.
Douglas et al., Wiley (1994)
 Inorganic Chemistry, 3rd ed., by G.L. Miessler and D.A. Tarr,
Prentice Hall (2004)
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Websites
 Course homepage: http://webct.ust.hk
 Useful links
• Department of Chemistry: http://www-chem.ust.hk/
• Textbook website: www.pearsoned.co.uk/housecroft
• Periodic table: For example,
http://www.webelements.com/
http://www.rsc.org/is/viselements.htm
http://pubs.acs.org/cen/80th/elements.html
 Conduct in classroom:
http://www.ust.hk/vpaao/conduct/con_classroom_Aug04.ppt
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Coordination Chemistry
• Ref.: Housecroft (Chap. 20), Shriver (Chap. 7)
• Introduction: the metals and ligands
• Crystal field theory: octahedral, tetrahedral, and
square planar geometry
• Spectrochemical series (strong/weak field ligands)
• Electron configurations: LFSE, LS and HS config.
• Spectral, magnetic and thermochemical properties
• Coordination equilibria, chelate effect
• M.O. diagram of ML6
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Coordination compounds (metal complexes)
Metal
n+
L
L
M
L
nX
L
L
L
Counter anion
Ligand
Common geometry
L
L
L
M
L
L
Tetrahedral
L
L
L
M
L
L
Square planar
M
L
L
L
Square pyramidal
L
L
L
L
M
L
L
M
L
L
L
Octahedral
L
L
Trigonal bipyramidal
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The metals
Transition elements (http://www.rsc.org/is/viselements.htm)
 Elements with incomplete d shell
(A) Position
First/ second/ third row TMs
 Size decreases down a group
 Lanthanide contraction (filling of f orbitals)
Sizes of 2nd row and 3rd row TMs are similar
Ion
Size/Å (CN = 6)
Cr3+
0.76
Mo3+
0.83
Ru3+ Ir3+
0.82 0.82
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(B) Early/late TMs
Early: on the LHS of the periodic table (e.g. Ti)
Late: on the RHS of the periodic table (e.g. Pt)
Usually, for metal complexes
 Early TM : high metal oxidation state, e.g. Ti(IV), V(V)
(high valent); hard metal ions (binds to hard ligands)
 Late TM : low metal oxidation state, e.g. Pt(II), Au(I)
(low valent); soft metal ions (binds to soft ligands)
 Why?
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Atomic radius
Ti
Cu
Atomic number
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IE
Ti
Cu
Atomic number
12
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Ligands
(A) Charge (formal charge)
• Neutral (e.g. :CO, :PR3, :NH3)
• Anionic (e.g. Cl-, O2-, CH3-)
• Cationic (rare!) (e.g. NO+, C7H7+)
(B) Hard/Soft properties
Hard : period 1 donor (NH3, OH2)
Soft : carbon (CO, CH3-, CH2=CH2) & period 2 donors
(PR3, SR2)
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(C) No. of donor atom
unidentate
NH3
ammonia
or ammine
N
pyridine
py
bidentate
NH2CH2CH2NH2
ethylenediamine
(en)
N
N
2,2'-bipyridine
bipy
tridentate
NH(CH2NH2)2
diethylenetriamine
(dien)
N
N
N
2,2':6',6"-terpyridine
terpy
Metal complexes with polydentate (chelating) ligands
are more stable than those with unidentate analogues.
Chelate effect
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(ii) p acceptors (p acids)
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Exercises
 Classify the following ligands as p donor, p acceptor,
or s ligands
• NMe3
• I• NO+
• CN• OH• H• CH3-
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Nomenclature
(1) Ligands in alphabetical order
(3) Indicate O.N. of metal (in Roman no.: I, II, 0)
(4) Indicate the no. of L and M (di, tri, tetra etc.).
Also bis, tris, tetrakis
(5) Anionic ligand  o;
e.g. Cl- (chloro), H- (hydrido), CN- (cyano)
(6) Anionic complexes => ate
e.g. Mn (manganate), Fe (ferrate), Cr (chromate) etc
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(7) Add structural prefixes,
e.g. cis/ trans, fac/ mer etc.
L
L
M
M
L
L
L
M
L
L
M
L
L
L
trans
cis
fac
mer
Examples:
K3[Mn(CN)6]
Tripotassium hexacyanomanganate(III)
Na2[Fe(CO)4]
Disodium tetracarbonylferrate(-II)
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Exercises
 Name the following compounds
 (1) [Mn2(CO)10], [Co2(CO)8]
 (2) [Ru(PPh3)4Cl2]
 (3) K2[Pt(CN)4]
 (4) [Cr(NH3)3(H2O)(OH)Cl][NO3]
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