Transitivity

Transitivity computes kinetic and thermodynamic parameters for chemical transformations and transport phenomena using phenomenological descriptions of rate processes (Aquilanti et al.).

Key Features:

• Transitivity function: The Transitivity function is defined as the reciprocal of the apparent activation energy and quantifies a reaction's propensity to proceed, supporting phenomenological kinetic models that deviate from Arrhenius behavior at low temperatures.
• Phenomenological evaluation: Procedures evaluate the temperature dependence of rate constants using both Arrhenius and Transitivity plots.
• Advanced kinetic models: Reaction rate constants are calculated via Transition-State Theory (TST) with one-dimensional tunneling corrections from Bell (1935), Bell (1958), Skodje and Truhlar, and the deformed-TST (d-TST) approach.
• Solvent effects: Kramers and Collins-Kimball formulations are incorporated to account for solvent effects on reaction rate constants.
• Molecular dynamics integration: An input-file generator facilitates molecular dynamics calculations with CPMD.
• Implementation: Implemented in Python.

Scientific Applications:

• Non-Arrhenius kinetics analysis: Analysis of systems exhibiting non-Arrhenius behavior at low temperatures using d-TST formulations and Transitivity plots.
• Rate constant estimation from electronic structure data: Documentation and estimation of kinetic and thermodynamic parameters from electronic structure calculations.
• Modeling transformations and transport phenomena: Computation of kinetic and thermodynamic parameters for chemical transformations and transport processes across varying conditions.

Methodology:

Methods explicitly include phenomenological formulations following Aquilanti et al., computation of Transitivity as the reciprocal of the apparent activation energy, evaluation via Arrhenius and Transitivity plots, TST with one-dimensional tunneling corrections (Bell 1935; Bell 1958; Skodje and Truhlar; d-TST), Kramers and Collins-Kimball solvent models, and generation of CPMD input files.