1. Determine the number of normal modes for H2O. Then sketch these modes and determine if...
4. Determine the symmetry and the number of all normal modes of vibration for methane and chloroform and identify the modes that are IR active and modes that are Raman active. How many bands would you "see” in the IR and Raman spectra for each compound?
2. (10 pts). CH3F belongs to C3e group. Determine the symmetry of all the normal modes using group theory. Find out the modes that are IR active. Find out the modes that are Raman active.
Vibrational modes EXERCISE 11.17: Determine the number of IR active vi- brational modes in each of the following molecules. Note: You will have to use symmetry arguments to determine which vibrations result in a net change in the molecular dipole moment. (a) SO, (b) NO (o) NO, (d) so, 2 (e) HCN (f) co (g) H,O (h) CO2 (i) NO
Geometry Point Group Reducible Representation For all atomic motions Vibrational modes Infrared-active modes Raman-active modes Number of IR absorptions Number of Raman emissions square planar
Cl 2. (15 points) For the SFsCl molecule: What is the point group? What is the total number of degrees of fredom -b gl 216 What is the total number of vibrational modes?3 What is the reducible representation and what are the irreducible representations of the vibrational modes? Identify which modes are Raman active, IR active, both active or neither. Determine the reducible representation. Then, determine the coefficients of the irreducible representations. Cl 2. (15 points) For the SFsCl molecule:...
1.4. Determine the number of IR active CO stretching modes for fac-[Mo(CO)=(NCCH3)3]. [HINT: Molecule has a point group. GBv]
Hydrogen cyanide (HCN) is a linear polyatomic molecule. i) calculate the number of normal modes of the molecule and ii) sketch the vibrational motion for each of these normal modes
For the following molecules, determine the number of translational, rotational, and vibrational normal modes 7. Translational Rotational Vibrational а. Н.О b. SiCl4 d. HCl e. SF6
8. Answer the following questions about CO2: a. What is the theoretical number vibrational modes of this molecule? b. What are factors that limit the number of observed vibrational modes? c. Explain why the symmetric stretch mode depicted here is Raman-active but IR- inactive.
Problem 1: Describe the vibrational normal modes of CO2 and H20, and then discuss which mode of each molecule is infrared active and which mode is inactive. (a) The four normal modes of CO2 v, (1388 cm-' v (2349 cm-) , (667 cm-' ,(667 cmt) (b) The three normal modes of H20 P, (3652 cm) (1595 cm) (3756 cm-)