HPRC SC 2019 Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; - PowerPoint PPT Presentation

HPRC SC 2019 Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; Fiedler, T.; Hampel, F.; Bhuvanesh, N.; Gladysz, J. A. J. Am. Chem. Soc. 2018 , 140 ,8463

MOLECULAR JUMP ROPE: MULTIRINGED METAL-COMPLEXES THAT REALLY KNOW HOW TO JUMP INTRODUCTION ▪ Molecular devices mimicking the properties of a m o l e c u l a r rotor where featuring a rotating and a static component is sought. ▪ Novel ''jump-rope'' process was observed in these '' parachute '' complexes while attempting to make molecular gyroscopes with a differentdesign. ▪ One potential application of these is the miniaturization of e l e c t r o n i c components. Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; Fiedler, T.; Hampel, F.; Bhuvanesh, N.; Gladysz, J. A. J. Am. Chem. Soc. 2018 , 140 ,8463

MOLECULAR JUMP ROPE: MULTIRINGED METAL-COMPLEXES THAT REALLY KNOW HOW TO JUMP SELECTED DATA ▪ Computing relative thermodynamic stability of byproducts in molecular devices P P X OC X X OC X Re P P Re P P Re OC CO OC CO Re OC CO P P OC CO CO CO + 3.8 Relative Stability + 2.0 0 – 0.2 – 0.4 – 3.4 X = Cl ( ) and Br ( ) – 3.6 Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; Fiedler, T.; Hampel, F.; Bhuvanesh, N.; Gladysz, J. A. J. Am. Chem. Soc. 2018 , 140 ,8463

MOLECULAR JUMP ROPE: MULTIRINGED METAL-COMPLEXES THAT REALLY KNOW HOW TO JUMP SELECTED DATA ▪ Predicting reaction outcome before performing experiments. n -13 O n -13 n* -13 O O n -13 n* -13 P P P n -13 n* -13 n -13 n* -15 n* -13 Cl n -13 Cl Cl O O O Pt P O P Pt Pt P P P P O Cl Pt n -13 Cl n -13 Cl O n -13 Pt Pt n -13 Cl Cl P P P not observed in Cl Cl Cl Cl O O n -13 O n* -13 + 15.7 n -13 experiments + 10.6 + 10.6 Relative Stability + 7.6 + 6.8 + 5.6 + 4.9 + 3.9 + 3.1 + 2.9 + 2.9 0 0 + 1.7 + 1.5 – 0.1 macro- cycle n n* size – 3.2 g /25 22 20 – 4.1 – 4.1 f /23 20 18 – 5.1 – 5.5 – 5.8 – 5.8 18 16 e /21 d /19 16 14 – 8.5 – 8.9 – 9.2 14 12 c /17 12 10 b /15 – 12.7 10 8 a /13 – 14.3 Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; Fiedler, T.; Hampel, F.; Bhuvanesh, N.; Gladysz, J. A. J. Am. Chem. Soc. 2018 , 140 ,8463

MOLECULAR JUMP ROPE: MULTIRINGED METAL-COMPLEXES THAT REALLY KNOW HOW TO JUMP SELECTED DATA ▪ Simulated spectroscopic data at different temperature to obtain rotational barriers . ▪ Experimental spectroscopic data at different temperatures. Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; Fiedler, T.; Hampel, F.; Bhuvanesh, N.; Gladysz, J. A. J. Am. Chem. Soc. 2018 , 140 ,8463

MOLECULAR JUMP ROPE: MULTIRINGED METAL-COMPLEXES THAT REALLY KNOW HOW TO JUMP METHOD ▪ A combination of molecular dynamics and electronic structure theory (DFT). ▪ HPRC resources: 28 cores (TERRA) and 20 cores (ADA), 150 h per optimization (incl. frequency calculations). ▪ Solvent models and dispersion corrections were also implemented in the atomistic quantum software package Gaussian 09. 1 E E 1 2 LOCALMINIMUM LOCALMINIMUM 2 MD DFT GLOBALMINIMUM Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; Fiedler, T.; Hampel, F.; Bhuvanesh, N.; Gladysz, J. A. J. Am. Chem. Soc. 2018 , 140 ,8463

MOLECULAR JUMP ROPE: MULTIRINGED METAL-COMPLEXES THAT REALLY KNOW HOW TO JUMP ACKNOWLEDGEMENTS ▪ A special thanks to Dr. Lisa M. Pérez (manager of LMS, Laboratory for Molecular Simulations at TAMU) and ▪ Professor Michael B. Hall (director of LMS) (co-advisor) Dr. John A. Gladysz Dr. Lisa M. Pérez Dr. Michael B. Hall Andreas Ehnbom ( www.andreasehnbom.se ) Joshi, H.; Kharel, S.; Ehnbom, A. ; Skopek, Hess, G. D.; Fiedler, T.; Hampel, F.; Bhuvanesh, N.; Gladysz, J. A. J. Am. Chem. Soc. 2018 , 140 ,8463