Naphthalene, C₁0H8 (shown at right) can be simplified by constructing SALC-AOs to serve as a basis. If we set the molecular plane to be the xy-plane, then the л-system is built from the 2pz orbitals on each carbon. Naphthalene is in the D2h point group and a table is provided at the end of the problem set showing all the symmetry operations on the 2pz orbitals. D2h Ag B1g B2g B3g Au В 14 B₂u B3u E 1 1 1 1 1 1 1 1 C2(z) C2(y) C₂(x) i 1 1 1 1 1 -1 1 -1 −1 1 -1 -1 1 1 1 1 1 1 -1 -1 -1 1 -1 -1 -1 -1 ܝܕ (a) Upon examining the symmetry transformations of the ten 2pz orbitals in naphthalene, one would find that they are the basis for the reducible representation given by Ê Ĉ₂(z) Ĉ₂(y) Ĉ₂ (x) î ô(xy) ô(xz) ô(yz) -2 0 0 -10 0 2 Fred (2pz) = 10 0 Reduce this representation into its irreducible representations using the D2h character table provided here. ܝ -1 ܝ ܝ ܝ ܝܕ -1 -1 o(xy) o(xz) 1 1 1 -1 -1 -1 -1 -1 -1 1 1 -1 1 1 177 2 -1 3 4 10 o(yz) 1 -1 -1 1 -1 1 1 -1 8 5 7 6 X

Determine the point group symmetry for following molecules a) SF-Cl b) trans-[CoBr2C14]³- c) CH3Br d) [NbAss]³- Nb

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What can you conclude about the symmetry of the C3H5+ ion as it actually exists, as regards the bond lengths and the distribution of the positive charge?

(a) to (c)

What do you expect the structure of Ge2H4 to look like ? sketch the structure in a clear three dimensional representation and give it's point group.

Find/show all possible symmetry operations and the point group of the following compounds by drawing their molecular structures. Additionally, decide whether the molecule is chiral or not. i) Decacarbonyldimanganese(0) ii) S4N4 iii) S2O8-2 iv) B2H6 v) Hydrazine

1. A fellow student claims that there is one more irreducible representation for the C2n point group, as follows. C2, Point Group E Ci On I (5) 1 -1 -1 -1 Clearly explain why this student must be incorrect.

The molecule CIF, belongs to the C4, point group. Use the character table below to answer the following questions. Cav A₁ کے ش E 2C C₂ 20 20d 1 1 1 1 1 Z A₂ 1 1 1 -1 -1 B₁ 1 -1 1 1 -1 B₂ 1 -1 1 -1 1 E 2 0 -2 0 0 (x, y) a) Draw CIF5 using a conventional cartesian coordinate system with the correct symmetry. (The Cl atom is in the center and is bonded to each of the 5 fluorine atoms.) b) Draw pictures showing how the p orbitals (x, y, and z) on Cl will transform under each operation of the group. c) Draw pictures showing how a i) dxy and a ii) dzz orbital on Cl would transform under each operation of the group. What are their Mulliken symbols? d) What are the irreducible representations for the SALCS of the 5 fluorine 2s orbitals? You do not need to draw a diagram or order the orbitals by energy, but for each molecular orbital symmetry, list all atomic orbitals and SALCs with that symmetry. Example: If this question were asking about the composition of the MOs of water (C₂, point group),…

Give all the symmetry elements in the following molecules, and assign the point group of each. a ) Xe(0) F4 b) cyclo-(C5H5) - c) IF 7 (pentagonal bipyramidal) d) Boric acid (right - assume it's rigid)