Chemistry 153 – Advanced Inorganic Chemistry Problem Set 5 (due ...

a. What is the vibrational frequency of the distorting mode in the excited state?b. What value of the Huang-Rhys parameter (SHR) gives the best fit to the lowest energyabsorption band?c. If the force constant for the Pt-Pt stretching mode is 1.0 mdyne/Å, what is the magnitudeof the distortion along the Pt-Pt coordinate in the excited state?The phosphorescence spectrum of crystalline Ba2Pt-POP at 10 K also displays rich finestructure in the Pt-Pt vibrational mode (bottom of the page). The vibronic peak positionsfor the phosphorescence band are given in the table below.d. What is the vibrational frequency of the distorting mode in the ground state?e. What value of the Huang-Rhys parameter (SHR) gives the best fit to thephosphorescence band?f. On the basis of your fit to the phosphorescence spectrum, what is the magnitude of thedistortion along the Pt-Pt coordinate in the excited state? How does this value compareto that extracted from the fit to the absorption spectrum?g. The Pt-Pt distance in the ground state of Pt-POP4! is 2.92 Å. On the basis of thestructured absorption and phosphorescence band profiles, what do you estimate for thePt-Pt distance in the excited state?h. Several time-resolved X-ray diffraction studies of Pt-POP 4 have appeared recently.Compare your estimated excited-state Pt-Pt bond distance to the results of one of thesestudies (include the reference of the study).Ba 2 POPPhosphorescencev , nm0 476.51 479.02 481.63 484.24 486.85 489.56 492.37 495.18 497.89 500.610 503.311 506.112 509.113 512.014 515.015 517.916 520.917 523.918 526.919 530.120 533.321 536.5