CY578 Wint.'16 Assignment 3

General Instructions: Assignments should be handwritten on A4 size papers. Include your name and roll Number at the top of the first page of each assignment. Do not submit in folders (most assignments require only one sheet; if you have more than one sheet use staple or pin). To be submitted NOT later than 31/3/16.

K₂CO₃ molecules can be trapped at low tempeartures, for example in frozen nitrogen (N₂ matrix). The I.R. spectrum of the matrix isolated molecules contain bands at 1472, 1317, 1010, 870 and 697 cm⁻¹. Uncoordinated ("gas phase") carbonate ions have stretching modes at 1460 and 1080 cm⁻¹. Comment on the possible structures of isolated K₂CO₃ molecule. (HINT: Do a group theoretical analysis of the vibrations of carbonate ion and changes expected when this ion coordinates to a metal ion through one or two oxygen atoms).