First-Principle Study of Molecular Springs under Shear Deformation Hong Seok Kang J. Bernholc 10.1021/jp0267353.s001 https://acs.figshare.com/articles/journal_contribution/First-Principle_Study_of_Molecular_Springs_under_Shear_Deformation/3724569 Recently synthesized tunable molecular springs are investigated theoretically using massively parallel density functional simulations with the generalized gradient approximation. The springs are salts of organosilver complexes that crystallize in structures with monoclinic symmetry. For springs with NO<sub>3</sub><sup>-</sup> (N-spring) and ClO<sub>4</sub><sup>-</sup> (Cl-spring) ions as negative balancers, we are able to refine their X-ray structures. Our calculations of total energies as functions of the nonorthogonal lattice angle β correctly reproduce the experimental equilibrium values of the angle for both the N- and Cl-springs. For the N-spring, our calculations reveal that the nitrate ions undergo concerted propeller rotations in the clockwise direction as the angle increases by 10° around the experimental value. For the Cl-spring, the rotations of chlorate ions are more enhanced in a limited range of the β angle, but they move in the counterclockwise direction. For the N-spring, the potential energy curve is symmetric and the shear modulus is about 0.01TPa. Calculations of the electronic density of states show that both springs are semiconductors. 2003-02-08 00:00:00 shear modulus states show calculation propeller rotations 0.01 TPa organosilver complexes density Shear Deformation Molecular Springs chlorate ions equilibrium values energy curve gradient approximation nitrate ions counterclockwise direction nonorthogonal lattice angle β β angle ClO 4 angle increases