Article
Chemistry, Multidisciplinary
Davide Mitoli, Jefferson Maul, Alessandro Erba
Summary: In the framework of density functional theory (DFT) simulations of molecules and materials, an efficient approach to calculate cubic and quartic interatomic force constants in the basis of normal modes was implemented in the CRYSTAL program. By applying group theory, the associated computational cost can be further reduced by exploiting point symmetry. The proposed group theoretical approach, implemented in the CRYSTAL program, shows significant speedup in high-symmetry molecular and periodic systems.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Chemistry, Multidisciplinary
Davide Mitoli, Jefferson Maul, Alessandro Erba
Summary: In the framework of density functional theory, a group theoretical approach was implemented to reduce computational cost and improve efficiency. The approach was assessed on six test case systems, showing significant speedup in high-symmetry molecular and periodic systems.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Biochemistry & Molecular Biology
Olivia A. A. Harwick, Ryan C. C. Fortenberry
Summary: Comets may contain various carbon oxide molecules on their surfaces and comae, with their silicon-substituted analogues possibly playing a role in interstellar dust formation. High-level quantum chemical data is provided to support potential astrophysical detection, as well as benchmarking for laboratory-based chemistry. The study suggests strong IR activity and potential for detection using JWST, with the possibility of observing dicarbon dioxide molecules in the microwave region of the electromagnetic spectrum.
Article
Biochemistry & Molecular Biology
Brent R. Westbrook, Ryan C. Fortenberry
Summary: Water borane and borinic acid have been proposed as intermediates in hydrogen generation from water and borane. Experimental investigation of their vibrational spectra is challenging, leading to the use of quantum chemical predictions. This study presents theoretical predictions of rotational and vibrational spectra for these molecules, benchmarked against experimental data.
Article
Chemistry, Physical
Silvan Kaser, Eric D. Boittier, Meenu Upadhyay, Markus Meuwly
Summary: In this study, a practical and affordable method for calculating anharmonic frequencies using machine-learned models is presented, which shows high accuracy in assigning experimentally measured frequencies to molecular motions of small- to medium-sized molecules.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Review
Spectroscopy
Mason B. Gardner, Brent R. Westbrook, Ryan C. Fortenberry, Timothy J. Lee
Summary: The CcCR quartic force field methodology is capable of computing rotational constants and vibrational frequencies with high precision, with deviations as low as 0.14% and 0.12% from experimental values, making it an accurate approach for spectroscopic data calculations.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Physics, Atomic, Molecular & Chemical
Olivia A. Harwick, Ryan C. Fortenberry
Summary: Aluminum forms strong bonds with several elements, but these bonds are rarely found in the interstellar medium. This study provides theoretical data and predictions for three cyclic aluminum oxide molecules, showing that they are weak-to-moderate infrared emitters and strong microwave emitters. Detection of these molecules in space could provide insights into the formation of aluminum-containing nanocrystals and interstellar dust, and the computed spectral data in this study can assist in their classification.
JOURNAL OF MOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Multidisciplinary
Arseniy A. Otlyotov, Yury Minenkov
Summary: The experimental gas-phase thermochemistry of alkali metal reactions with acetonitrile/ammonia is reproduced. Three approximations are tested and the modified scaled RRHO scheme (msRRHO) provides the most accurate reaction entropies. The msRRHO approach is also used to calculate the enthalpy contribution and reaction Gibbs free energies, ensuring internal consistency. The final increment Gibbs free energy MUEs for msRRHO, sRRHO(100) and sRRHO schemes are 1.2, 3.6 and 3.1 kcal mol(-1).
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Langping Zhou, Jingjing Cui, Zhihao Yu, Dongxuan Zou, Weibing Zhang, Junhong Qian
Summary: The fluorescent probe NFP-G was designed and synthesized with beta-D-galactose as the targeted unit and hydrazine as the recognition group for formaldehyde detection. Experimental results showed that NFP-G exhibited highly fluorescent responses towards formaldehyde, with good selectivity and competition over potentially interfering species. The sensing mechanism of the probes was studied through theoretical calculation, high performance liquid chromatography, and mass spectrum analysis.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Biochemistry & Molecular Biology
Caroline A. de Almeida, Larissa P. N. M. Pinto, Helio F. Dos Santos, Diego F. S. Paschoal
Summary: This study discusses the impact of PTBS and relativistic effects on the vibrational frequencies and intramolecular force constants of cisplatin, finding that the inclusion of relativistic effects improves the description of the cisplatin structure. Additionally, the PBE0 functional outperformed B3LYP in predicting vibrational frequencies, making it a good choice for studying Pt complexes.
JOURNAL OF MOLECULAR MODELING
(2021)
Article
Chemistry, Physical
Megan C. Davis, Noah R. Garrett, Ryan C. Fortenberry
Summary: High-level rovibrational characterization of methanediol confirms its gas phase preparation and provides important parameters for further studies and astronomical detection.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Optics
Debdatta Ray, Andrei Kiselev, Olivier J. F. Martin
Summary: This study systematically investigates the evolution of multipoles and spectra for a hybrid metal-dielectric nanoantenna as its dimensions vary. By adjusting the height of the Ag on the Si cylinder and introducing insulating spacing, magnetic light at different energy levels is demonstrated. Furthermore, variations in the radius of the Ag disk are explored to observe the anapole state and narrow spectral features.
Article
Chemistry, Physical
Nandini Mukherjee
Summary: The precision of quantum states in the incoming channel determines the amount of information that scattering experiments can provide. In this article, we discuss the use of H2 and its isotopologues as targets for cold inelastic scattering experiments. By preparing the target in a precisely defined rovibrational quantum state and using a technique called Stark-induced adiabatic Raman passage, we can control the dynamics of anisotropic interactions. Through various examples of rotationally inelastic cold scattering experiments, we show how this technique allows for a direct comparison with theoretical computations, aiding in accurate modeling of molecular interaction potentials.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Xin Xu, Jun Chen, Xiaoxiao Lu, Wei Fang, Shu Liu, Dong H. Zhang
Summary: In the OH + HCl reaction, the presence of resonance states greatly induces quantum tunneling of hydrogen atoms, causing the reaction rates to deviate substantially from Arrhenius behavior at low temperature.
Article
Chemistry, Physical
J. C. J. Koelemeij
Summary: This paper revisits the problem of separating the purely rovibrational and hyperfine contributions to observed rovibrational transition frequencies. It presents an alternative approach to remove theoretically computed hyperfine shifts from observed frequencies, and discusses the effect of correlations between uncertainties on the derived transition frequency. The paper also proposes a method to quantify the additional shift and uncertainty, which has implications for other applications of spectroscopic data, such as determining fundamental physical constants.
