P11E.2 Suppose that three conformations are proposed for the nonlinear molecule H,O, (1, 2, and 3). The infrared absorption spectrum of gaseous H,O, has bands at 870, 1370, 2869, and 3417 cm. The Raman spectrum of the same sample has bands at 877, 1408, 1435, and 3407 cm. All bands correspond to fundamental vibrational wavenumbers and you may assume that: (a) the 870 and 877 cm bands arise from the same normal mode, and (b) the 3417 and 3407 cm bands arise from the same normal mode. (i) If H,O, were linear, how many normal modes of vibration would it have? (ii) Give the symmetry point group of each of the three proposed conformations of nonlinear H,O,. (iii) Determine which of the proposed conformations is inconsistent with the spectroscopic data. Explain your reasoning. 2

P11E.2 Suppose that three conformations are proposed for the nonlinear molecule H,O, (1, 2, and 3). The infrared absorption spectrum of gaseous H,O, has bands at 870, 1370, 2869, and 3417 cm. The Raman spectrum of the same sample has bands at 877, 1408, 1435, and 3407 cm. All bands correspond to fundamental vibrational wavenumbers and you may assume that: (a) the 870 and 877 cm bands arise from the same normal mode, and (b) the 3417 and 3407 cm bands arise from the same normal mode. (i) If H,O, were linear, how many normal modes of vibration would it have? (ii) Give the symmetry point group of each of the three proposed conformations of nonlinear H,O,. (iii) Determine which of the proposed conformations is inconsistent with the spectroscopic data. Explain your reasoning. 2

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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