Ligand Group Orbitals Created by Chip Nataro (Lafayette College
and posted on VIPEr (www.ionicviper.org) on March 27, Copyright
Chip Nataro This work is licensed under the Creative Commons
Attribution Non-commercial Share Alike License. What can you do to
the following shapes so they are indistinguishable before and
after? Created by Chip Nataro (Lafayette College and posted on
VIPEr (www.ionicviper.org) on March 27, Copyright Chip Nataro This
work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. Proper rotation (C n ) Define
an axis and rotate counterclockwise 360/n is how many o the
rotation is Example NH 3 Created by Chip Nataro (Lafayette College
and posted on VIPEr (www.ionicviper.org) on March 27, Copyright
Chip Nataro This work is licensed under the Creative Commons
Attribution Non-commercial Share Alike License. Reflection ( ) Pass
a mirror plane through an object Types of mirror planes Horizontal
( h ) perpendicular to the PA Vertical ( v ) contains PA passes
through outer atoms Dihedral ( d ) contains PA misses outer atoms
Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Improper rotation (S n ) n have same meaning
as proper rotations Rotate by n along an axis Reflect perpendicular
to that axis Can be coincidental with a proper rotation axis Not of
major concern for us Created by Chip Nataro (Lafayette College and
posted on VIPEr (www.ionicviper.org) on March 27, Copyright Chip
Nataro This work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. Set of symmetry operations that
describes a molecule Mathematical treatment of groups Created by
Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Is the molecule of low symmetry? C1, Cs, C i
Is the molecule of high symmetry? Td, Oh, C v, D h, I h
Highest-order rotation axis (Cn) Perpendicular C2s? D groups h? Dnh
d? DndDn C or Sn groups h?h? Cnh v? CnvS2n? S2nCn Yes C 1 No
symmetry C s Just a mirror plane C i Just an inversion center No
High symmetry groups typically have many symmetry operations
Consider SF 6 Created by Chip Nataro (Lafayette College and posted
on VIPEr (www.ionicviper.org) on March 27, Copyright Chip Nataro
This work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. Determine the point group for
NH 3 Cyclopropane Created by Chip Nataro (Lafayette College and
posted on VIPEr (www.ionicviper.org) on March 27, Copyright Chip
Nataro This work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. Is the molecule of low
symmetry? C1, Cs, C i Is the molecule of high symmetry? Td, Oh, C
v, D h, I h Highest-order rotation axis (Cn) Perpendicular C2s? D
groups h? Dnh d? DndDn C or Sn groups h?h? Cnh v? CnvS2n? S2nCn Yes
No Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Determine the point group for NH 3 C 3v
Cyclopropane D 3h Created by Chip Nataro (Lafayette College and
posted on VIPEr (www.ionicviper.org) on March 27, Copyright Chip
Nataro This work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. Draw a Lewis structure and
assign VSEPR geometry Assign a point group to the molecular
geometry Determine the VB hybrid orbitals for the electronic
geometry of the central atom Use the VB hybrid orbitals as
generator functions Generate the Ligand Group Orbitals (LGOs) by
combining the ligand -orbitals to obtain an orbital with the same
symmetry as the generator function Assign symmetry labels to the
LGOs from the character table by matching the label of the
generator function Created by Chip Nataro (Lafayette College and
posted on VIPEr (www.ionicviper.org) on March 27, Copyright Chip
Nataro This work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. Draw the Lewis structure B has
3 valence electrons H has 1 valence electron B.... H. H. H The
molecular geometry is? AX 3 trigonal planar What is the point
group? Created by Chip Nataro (Lafayette College and posted on
VIPEr (www.ionicviper.org) on March 27, Copyright Chip Nataro This
work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. Is the molecule of low
symmetry? C1, Cs, C i Is the molecule of high symmetry? Td, Oh, C
v, D h, I h Highest-order rotation axis (Cn) Perpendicular C2s? D
groups h? Dnh d? DndDn C or Sn groups h?h? Cnh v? CnvS2n? S2nCn Yes
No D 3h Created by Chip Nataro (Lafayette College and posted on
VIPEr (www.ionicviper.org) on March 27, Copyright Chip Nataro This
work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. The electron geometry is AX 3 E
0 This is an electron deficient molecule From General Chemistry sum
X and E 2 sp 3 sp 2 4 sp 3 5 sp 3 d 6 sp 3 d 2 Created by Chip
Nataro (Lafayette College and posted on VIPEr (www.ionicviper.org)
on March 27, Copyright Chip Nataro This work is licensed under the
Creative Commons Attribution Non-commercial Share Alike License.
Considering the boron atom We need to assign axes An abbreviated
character table y x z D 3h Orbital A1A1 s A2A2 EE p x, p y A 1 A 2
pzpz E A1A1 EE EE A 2 Created by Chip Nataro (Lafayette College and
posted on VIPEr (www.ionicviper.org) on March 27, Copyright Chip
Nataro This work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. A1A1 EE EE A 2 Created by Chip
Nataro (Lafayette College and posted on VIPEr (www.ionicviper.org)
on March 27, Copyright Chip Nataro This work is licensed under the
Creative Commons Attribution Non-commercial Share Alike License. E
B3 H BH 3 A1A1 A 1 ( ) EE E ( ) A 2 (nb) A 2 EE EE EE A1A1 A 1 ( )
E ( ) Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. A 1 ( ) E ( ) A 2 (nb) A 1 ( ) E ( ) Created
by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Draw the Lewis structure What is the molecular
geometry? What is the point group?.. AX 2 bent based on tetrahedral
Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Is the molecule of low symmetry? C1, Cs, C i
Is the molecule of high symmetry? Td, Oh, C v, D h, I h
Highest-order rotation axis (Cn) Perpendicular C2s? D groups h? Dnh
d? DndDn C or Sn groups h?h? Cnh v? CnvS2n? S2nCn Yes No C 2v
Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Whats the electron geometry? What is the
hybridization on oxygen? Assign axes AX 2 E 2 sp 3 z x y Created by
Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. C 2v Orbital A1A1 s, p z A2A2 B1B1 pxpx B2B2
pypy A1A1 B2B2 A1A1 B1B1 Are there any that cannot interact with
the H atoms? GeneratorSymmetryLigandsLone pair sA1A1 Yes pzpz A1A1
pypy B2B2 NoYes pxpx B1B1 No Can interact with Created by Chip
Nataro (Lafayette College and posted on VIPEr (www.ionicviper.org)
on March 27, Copyright Chip Nataro This work is licensed under the
Creative Commons Attribution Non-commercial Share Alike License.
A1A1 A1A1 B1B1 B2B2 E O2 H H2OH2O A1A1 A1 ()A1 () B1B1 B 1 ( ) A 1
(lp) B 2 (lp) B2B2 A1A1 B1B1 A1A1 B1 ()B1 () A 1 ( ) Created by
Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Draw the Lewis structure What is the molecular
geometry? What is the point group? AX 5 trigonal bipyramidal
Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Is the molecule of low symmetry? C1, Cs, C i
Is the molecule of high symmetry? Td, Oh, C v, D h, I h
Highest-order rotation axis (Cn) Perpendicular C2s? D groups h? Dnh
d? DndDn C or Sn groups h?h? Cnh v? CnvS2n? S2nCn Yes No D 3h
Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. Whats the electron geometry? What is the
hybridization on phosphorus? Assign axes AX 5 E 0 sp 3 d z x y
Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License. D 3h Orbital A1A1 s, d z 2 A2A2 EE p x, p y A
1 A 2 pzpz E A1A1 EE EE A 2 A1A1 Created by Chip Nataro (Lafayette
College and posted on VIPEr (www.ionicviper.org) on March 27,
Copyright Chip Nataro This work is licensed under the Creative
Commons Attribution Non-commercial Share Alike License. A1A1 EE EE
A 2 A1A1 X Created by Chip Nataro (Lafayette College and posted on
VIPEr (www.ionicviper.org) on March 27, Copyright Chip Nataro This
work is licensed under the Creative Commons Attribution
Non-commercial Share Alike License. E PPF 5 5 F A 2 ( *) E ( *) A 1
( *) A 2 ( ) E ( ) A 1 ( ) A 2 E A1A1 A1A1 A 1 (nb) A 2 E A1A1
Created by Chip Nataro (Lafayette College and posted on VIPEr
(www.ionicviper.org) on March 27, Copyright Chip Nataro This work
is licensed under the Creative Commons Attribution Non-commercial
Share Alike License.