Stress tensor eigenvector following with next‐generation quantum theory of atoms in molecules

Abstract

The eigenvectors of the electronic stress tensor have been identified as useful for the prediction of chemical reactivity because they determine the most preferred directions to move the bonds.A new 3-D vector based interpretation of the chemical bond that we refer to as the bond-path framework set B provides a version of the quantum theory of atoms in molecules (QTAIM) beyond the minimum definition for bonding that is particularly suitable for understanding changes in molecular electronic structure that occur during reactions. We demonstrate that the most preferred direction for bond motion using the stress tensor corresponds to the most compressible direction and not to the least compressible direction as previously reported. We show the necessity for a directional approach constructed using the eigenvectors along the entire bond-length and demonstrate the insufficiency of scalar measures for capturing the nature of the stress tensor within the QTAIM partitioning. K E Y W O R D Sbond-path framework set, QTAIM, stress tensor, torsion

Next‐generation quantum theory of atoms in molecules for the photochemical ring‐opening reactions of oxirane

“…We refer to the next‐generation QTAIM interpretation of the chemical bond as the bond‐path framework set, denoted by B, where B = { p , q , r } with the consequence that for a given electronic state a bond is comprised of three “linkages”; p , q , and r associated with the e 1 , e 2 , and e 3 eigenvectors, respectively. Where the p , q , and r are 3‐D paths constructed from the values of the least ( e 1 ) and most ( e 2 ) preferred directions of electronic charge density accumulation ρ ( r ) along the bond path, referred to as ( r ).…”

Next‐generation quantum theory of atoms in molecules for the S1/S0 conical intersections in dynamics trajectories of a light‐driven rotary molecular motor

“…The next‐generation QTAIM interpretation of the chemical bond, defined as bond‐path framework set B = { p , q , r }, and for a given electronic state, a bond is comprised of three “3D linkages,” where p , q , and r associated with the e 1 , e 2 , and e 3 eigenvectors, respectively . In this investigation, we also consider the first excited state ( S 1 ), therefore B comprises six strands constructed from the least ( p 0 , p 1 ) and most ( q 0 , q 1 ) preferred directions of directions of charge density accumulation in addition to the bond path ( r 0 , r 1 ).…”

Control of Chirality, Bond flexing and Anharmonicity in an Electric Field

“…The background of QTAIM and next generation QTAIM (NG-QTAIM) [34], [50]- [55] with explanations is provided in theSupplementary Materials S1 , along with the procedure to generate the stress tensor trajectories T σ (s ). In this investigation we will use Bader's formulation of the stress tensor [32] within the QTAIM partitioning, which is a standard option in the QTAIM AIMAll [56] suite.…”

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