Question

Question 1,d) (i,ii) please
b and c would be a nice addition x)

1) A peak observed at 1690 cm' in the mid-IR spectrum of quanine is assigned to the carbonyl stretching vibration. b) Predict the approximate position of the first overtone peak from this vibration (give your answer in cm), and comment on the intensity of this overtone peak compared to the fundamental at 1690 cm. (2 marks) c) Where would you expect to observe a peak due to the carbonyl stretch vibration in the vibrational-Raman spectrum of guanine, if the 514.5 nm line of an argon ion laser was used as the incident light source? Express your answer in both relative reciprocal centimetres (relative cm') and in nanometers (nm). (3 marks) i) What would the peak position be if the 488 nm line from the argon-ion laser was used instead of the 514.5 nm line? Give you answer in both nm and in relative cm-1 ii) What would the relative intensity of the peak be if the 488 nm line from the argon-ion laser was used instead of the 514.5 nm line? (Assume that the power output of the laser was the same at both wavelengths.) (4 marks)

Answer 1

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