Spectroscopy
The type of spectroscopy that can be approximated by solving the particle in a box problem
What is Uv-vis spectroscopy?
1. not infinite
2. can't be 0 everywhere
3. single valued
4. continuous and derivative is continuous
The number of rotational axes in staggered ethane
a. 2
b. 3
c. 4
d. 5
4
The term symbol for potassium (4s1)
2S1/2
Name the gross selection rules for rotational Raman spectroscopy.
anisotropically polarizable
The type of spectroscopy that can be used to determine the dissociation energy of a molecule
What is vibrational spectroscopy?
Which of the following operators commute.
1. E and p
2. L2 and x
3. Lx and Ly
4. x and p
E and p
How many symmetry planes are present in water?
2
Gallium arsenide is a common semiconductor used in many electrical devices. What is the term symbol for GaAs?
1Sigma
What is the gross selection rule for microwave rotational spectroscopy?
molecule must be polar
In a rotational Raman experiment the separation between lines is found to be 16.4 cm-1. What is the value of the rotational constant?
What is 4.1 cm^-1
The quantum system in which energy levels are equally spaced.
What is harmonic oscillator
The difference between the 3 types of mirror planes
vertical contains principal axis, horizontal is perpendicular, dihedral bisects 2 C2 axes
Spin orbit coupling plays an important role in deriving the term symbols. What two entities are coupling together and what is the resulting quantum number?
spin angular momentum and orbital angular momentum, j(J)
What type of radiation is technically forbidden according to the selection rules and what rule is broken?
phosphorescence, spin flip
We discussed 3 types of spectroscopy. List them in order of lowest to highest energy for a transition.
What is rotational, vibrational, electronic.
The expression for energy of a particle on a sphere
l(l+1)hbar2/2I
Which of the following molecules has an improper rotation?
1. methane
2. water
3. thiocyanate (SCN-)
4. ethane (eclipsed)
methane
What are the two term symbols associated with a phosphorescence experiment of a homonuclear diatomic molecule?
1Sigmag and 3Sigmag
Which of the following transitions is NOT allowed?
1. 3P1 → 3D1
2. 2S3/2 → 2S1/2
3. 3D3 → 3S2
4. 2D3/2 → 2F5/2
3D3 → 3S2
What is the spacing between lines in a rovibrational IR spectrum?
2B
The expression for energy of a harmonic oscillator
(v+1/2)hbar omega
The point group of benzene
D6h
Which of the following is a viable term symbol for an excited aluminum atom with the electron configuration of [Ne] 3s23p14p1
1. 3P3
2. 1S1/2
3. 1P3/2
4. 3D4
3P3
What mathematical expression governs whether a given transition will be allowed?
integral psi * u psi