CHEM 3303 - Supplementary Problems - Part 2 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Review: Linear Combinations of Atomic Orbitals (LCAO's) Question 1 a. sp3d: Square Pyramidal, axial-base angle = 90° b. sp3d: Square Pyramidal, axial-base angle > 90° Symmetry Adapted Linear Combinations (SALCs) Question 1 a. PdCl42- (square planar) Point Group = D4h
Reduces to A1g + B1g + Eu b. SiCl4 Point Group = Td
Reduces to A1 + T2 c. cis-PtF2Cl22- Point Group = C2v
Reduces to A1 + B1 for both F and Cl d. SF6 Point Group = Oh
Reduces to A1g + Eg + T1u Question 2 a. PdCl42- (square planar) b. SiCl4 c. cis-PtF2Cl22- d. SF6 Molecular Orbital Diagrams (σ-bonding) Question 1 a. trans-SF2Cl4 Point Group = D4h
Γσ(F) reduces to A1g + A2u Γσ(Cl) reduces to A1g + B1g + Eu b. NH4+ Point Group = Td
Reduces to A1 + T2 c. SF6 Point Group = Oh
Reduces to A1g + Eg + T1u Molecular Orbital Diagrams (π-bonding) Question 1 a. SiF4 Point Group = Td All sets of vectors lie along a C3 rotation axis, therefore the p orbitals cannot be separated into subsets
Reduces to E + T1 + T2 Note: Si used s, px, py and pz orbitals for σ-bonding b. GeH2Cl2 Point Group = C2v Only the Cl atoms can participate in π-bonding. The Cl atoms lie along a C1 rotation axis, therefore the p orbitals can be separated into perpendicular and parallel to the Cl-Ge-Cl plane.
Γπ⊥ reduces to A2 + B2 Γπ // reduces to A1 + B1 Hint: Draw the SALCs to determine the relative order Note: Ge used s, px, py and pz orbitals for σ-bonding c. SnCl62- Point Group = Oh All sets of vectors lie along a C4 rotation axis, therefore the p orbitals cannot be separated into subsets
Reduces to A1g + Eg + T1u Question 2 a. π-bonding perpendicular to the plane Point Group = D4h The vectors lie along a C2 rotation axis, there the p orbitals can be separated into one set of four perpendicular to the plane and one set of four parallel to the plane. Recall that d block elements use ns, np and (n-1)d orbitals for bonding, and that (n-1)d orbitals are lower in energy than ns and np orbitals.
Reduces to Eg + A2u + B2u b. π-bonding parallel to the plane Point Group = D4h The vectors lie along a C2 rotation axis, there the p orbitals can be separated into one set of four perpendicular to the plane and one set of four parallel to the plane. Recall that d block elements use ns, np and (n-1)d orbitals for bonding, and that (n-1)d orbitals are lower in energy than ns and np orbitals.
Reduces to A2g + B2g + Eu |