# HMWR3 - 2 Group Theory(30 pts Evaluate the products between...

This preview shows page 1. Sign up to view the full content.

110B Physical Chemistry Homework #2: assigned 2/2/11; due 2/14/11 in class 1. Quantum Chemistry Calculations (40 pts) Within the context of quantum chemistry calculations, what does one mean by basis set? Describe at least three different choices of basis set for a quantum mechanical calculations. Show that the overlap integral of the two normalized Gaussian functions g1 = (2 α / π ) 3/4 exp [ - α (r- R A ) 2 ] centered at R A and g2 = (2 β / π ) 3/4 exp [ - β (r- R B ) 2 ] centered at R B is proportional to exp [- αβ ( R A - R B ) 2 /( α + β )]. Here A and B denote two atoms in a molecule and r denotes electronic coordinates. Discuss how this overlap varies as a function of the distance between the two atoms, and how large it is when the two atoms are at an infinite distance. What would the value of the overlap be if the A-B distance went to zero?
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 2. Group Theory (30 pts) Evaluate the products between the symmetry operations of the point group C 2v . Give examples of molecules (at least 3) whose symmetry is represented by the C 2v group. Consider a water molecule and substitute one hydrogen atom with deuterium. Does the symmetry of the molecule change. If so, explain how. List the symmetry elements for the trigonal planar molecule SO 3 . 3. Hueckel approximation (30 pts) Compute the Hueckel π electron energy (the sum of all energies of orbitals occupied by p electrons, taking into account spin multiplicity) of trimethylenemetane (C 4 H 6 ) and compare it with that of two isolated ethane molecules....
View Full Document

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern