Eyringpy is a modular program for calculating thermochemical properties and rate constants for reactions in the gas phase and in solution. The code is written in Python and it has a user‐friendly interface and a simple input format. Unimolecular and bimolecular reactions with one and two products are supported. Thermochemical properties are estimated through canonical ensemble and rate constants are computed according to the transition state theory. One‐dimensional Wigner and Eckart tunneling corrections are also available. Rate constants of bimolecular reactions involving the formation of pre‐reactive complexes are also estimated. To compute rate constants in solution, Eyringpy uses the Collins–Kimball theory to include the diffusion‐limit, the Marcus theory for electron transfer processes, and the molar fractions to account for the solvent pH effect.

Unlike other atoms, a planar tetracoordinate fluorine atom is elusive. So far, there are no theoretical or experimental reports suggesting their existence. Herein, we introduce the first six combinations (FIn4+,...

Hindered rotations are common in nature and can greatly affect thermodynamic properties. Typically, the standard rigid-rotor harmonic-oscillator approximation is used to compute thermodynamic properties; however, it often leads to serious errors, particularly for molecules with hindered rotations. Hence, to reach accurate thermodynamic predictions for such cases, the hindered rotor approximation must be applied. Different methods to compute thermodynamic properties for molecules with hindered rotations are available. Herein, we review the theoretical basis of different methods, their accuracy, and applicability. We also present the different algorithms to identify hindered rotors and obtain the input parameters for the hindered rotor model, and the software available to compute thermodynamic properties under this scheme.

The mechanism for the walk rearrangement in Dewar thiophenes has been clarified theoretically by studying the evolution of chemical bonds along the intrinsic reaction coordinates. Substituent effects on the overall mechanism are assessed by using combinations of the ring (R = H, CF3) and traveling (X = S, S = O, and CH2) groups. The origins of fluxionality in the S–oxide of perfluorotetramethyl Dewar thiophene are uncovered in this work. Dewar rearrangements are chemical processes that occur with a high degree of synchronicity. These changes are directly related to the activation energy.

To analyze the evolution of a chemical property along the reaction path, it is necessary to extract all the information from a set of electronic structure computations. However, this process is time-consuming and prone to human error. Here we introduce intrinsic reaction coordinate (IRC)-Analysis, a new extension in Eyringpy, to monitor the evolution of chemical properties along the intrinsic reaction coordinate, including the complete reaction force analysis. IRC-Analysis collects the entire data set for each snapshot of the reaction coordinate, avoiding human error in data capture, and allowing the study of several chemical reactions in seconds. Eyringpy is written in Python, has a simple input format, and no programming skills are required.Python's Matplotlib library is used for plotting the evolution of the properties along the reaction coordinate. This version can analyze the evolution of bond distances, angles, Wiberg bond indices, natural charges, dipole moments, and orbital energies (and related properties).

The preference for concave mode binding of the CpM unit with sumanene in CpM(η 6 -sumanene) + (M = Fe, Ru, Os) over the convex mode is analyzed by various density functional theory based methods including (or not) dispersion and solvent effects. In the case of the iron complex, the concave-bound isomer becomes energetically more favorable than the convex form only after the proper inclusion of dispersion effects, highlighting the importance of such contributions to stabilize the former arrangement. For the ruthenium complex, both the dispersion and solvent effects should be taken into account to provide a correct trend. The noncovalent interaction index corroborates the role of dispersion in concave selectivity. Our computations also show that the presence of the counterion is not relevant for this selectivity, discarding the previously reported argument made by Okumura et al.

The mechanisms proposed for the synthesis of diarylamines from diarylsulfinamides are revisited via quantum chemical computations, verifying the 3-exotrig Smiles rearrangement as the most viable pathway. Diarylamine precursors with sterically hindered, electron-rich, or electron-deficient N-aryl rings do not alter the barriers. However, the effects of the substituent on the S-aryl ring of monosubstituted, dimonosubstituted, and trisubstituted diarylsulfinamides can drastically change the rearrangement barriers. Furthermore, our results of rate constants computed at different temperatures show that the temperature rise favors the 3-exo-trig Smiles rearrangement reactions.

Unlike other atoms, planar tetracoordinate fluorines are elusive. So far, there are no theoretical or experimental reports suggesting their existence. Herein, we introduce the first six combinations, whose global minima contain a planar tetracoordinate fluorine. All of them are surrounded exclusively by atoms of group 13. The bonding scheme shown by these species is entirely different from analogous systems with carbon, nitrogen, or oxygen atoms. The magnetic response characterizes these systems mostly σ-aromatic. The planar form is somewhat stabilized by subtle ionic interactions of the fluorine with the peripheral atoms, forming an adequately sized cavity. <br>