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1. Chain Exchange Kinetics of Asymmetric B ₁ AB ₂ Linear Triblock and AB ₁ B ₂ Branched Triblock Copolymers

   https://doi.org/10.1021/acs.macromol.7b01046  

   Peters, Andrew J.; Lodge, Timothy P. (August 2017, Macromolecules)
2. A polarizability driven ab initio molecular dynamics approach to stimulating Raman activity: Application to C ₂₀

   https://doi.org/10.1080/00268976.2021.1939453  

   Pierre-Jacques, Dominick; Tyler, Ciara; Dyke, Jason; Kaledin, Alexey L.; Kaledin, Martina (June 2021, Molecular Physics)

   null (Ed.)

   We describe a novel variant of the driven molecular dynamics (DMD) method derived for probing Raman active vibrations. The method is an extension of the conventional alpha-DMD formulation for simulating IR activity by means of coupling an oscillating electric field to the molecule’s dipole moment, miu, and inducing absorption of energy via tuning the field to a resonant frequency. In the present work, we modify the above prescription to invoke Raman activity by coupling two electric fields, i.e., a “Pump” photon of frequency wP and a Stokes photon of frequency wS to the molecule’s polarizability tensor, alpha, with the difference in the frequencies of the two photons w = wP - wS corresponding to the Stokes Raman shift. If a particular w is close to a Raman active vibrational frequency, energy absorption by the molecule ensues. Varying w over the desired frequency range allows identifying and assigning all Raman active vibrational modes, including anharmonic corrections, in the range by means of trajectory analysis. We show that only one element of the full polarizability tensor, and its nuclear derivative, is needed for an alpha-DMD trajectory, making this method well suited for ab initio dynamics implementation. Numerical results using first-principles calculations are presented and discussed for the vibrational fundamentals, combination bands, overtones of H2O, CH4, and the C20 fullerene. 

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3. AB ₂ X ₆ Compounds and the Stabilization of Trirutile Oxides

   https://doi.org/10.1021/acs.inorgchem.1c01366  

   Schueller, Emily C.; Oey, Yuzki M.; Miller, Kyle D.; Wyckoff, Kira E.; Zhang, Ruining; Zhang, William; Wilson, Stephen D.; Rondinelli, James M.; Seshadri, Ram (June 2021, Inorganic Chemistry)

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4. Ab initio thermal rate coefficients for H + NH ₃ ⇌ H ₂ + NH ₂

   https://doi.org/10.1002/kin.21255  

   Nguyen, Thanh Lam; Stanton, John F. (February 2019, International Journal of Chemical Kinetics)
5. Investigation of pressure-driven superconductivity in TlInTe ₂ : an ab initio study

   https://doi.org/10.1088/1402-4896/ad59dc  

   Renskers, Christopher; Margine, Elena_R (July 2024, Physica Scripta)

   Abstract The Zintl compound TlInTe₂is an intriguing material because of its outstanding thermoelectric properties at ambient pressure. Interestingly, it has recently been found that TlInTe₂exhibits a V-shape dependence of the superconducting critical temperature (T_c) under increasing pressure, which has been linked to the reversed behavior of the Raman active A_gphonon mode and anharmonic effects. In this study, we have performed first-principles calculations of the electron-phonon interactions and the superconducting properties of TlInTe₂in order to understand this unusual pressure-induced response. In contrast to experiment, we find a dome-shaped pressure-induced dependence ofT_cwith a maximum value of 0.23 K at 18 GPa, significantly lower than the experimental results. Electron doping has the potential to adjust theT_cto fall within the experimental range, but it necessitates considerably high levels of doping. Furthermore, our analysis of the phonon spectra and phonon lifetimes, including anharmonic effects, show that anharmonicity is unlikely to influence the superconducting properties of TlInTe₂. It remains an open question whether there is indeed an unusual V-shapeT_cdependence with pressure or whether the phonon-mediated theory of superconductivity used here breaks down in this system. 

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