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| Economics Ph.D.: Publications since January 2023List all publications in the database. :chronological by author listing:%% @article{fds375216, Author = {Mendis, KC and Li, X and Valdiviezo, J and Banziger, SD and Zhang, P and Ren, T and Beratan, DN and Rubtsov, IV}, Title = {Electron transfer rate modulation with mid-IR in butadiyne-bridged donor-bridge-acceptor compounds.}, Journal = {Physical chemistry chemical physics : PCCP}, Volume = {26}, Number = {3}, Pages = {1819-1828}, Year = {2024}, Month = {January}, url = {http://dx.doi.org/10.1039/d3cp03175f}, Abstract = {Controlling electron transfer (ET) processes in donor-bridge-acceptor (DBA) compounds by mid-IR excitation can enhance our understanding of the ET dynamics and may find practical applications in molecular sensing and molecular-scale electronics. Alkyne moieties are attractive to serve as ET bridges, as they offer the possibility of fast ET and present convenient vibrational modes to perturb the ET dynamics. Yet, these bridges introduce complexity because of the strong torsion angle dependence of the ET rates and transition dipoles among electronic states and a shallow torsion barrier. In this study, we implemented ultrafast 3-pulse laser spectroscopy to investigate how the ET from the dimethyl aniline (D) electron donor to the <i>N</i>-isopropyl-1,8-napthalimide (NAP) electron acceptor can be altered by exciting the CC stretching mode (<i>ν</i><sub>CC</sub>) of the butadiyne bridge linking the donor and acceptor. The electron transfer was initiated by electronically exciting the acceptor moiety at 400 nm, followed by vibrational excitation of the alkyne, <i>ν</i><sub>CC</sub>, and detecting the changes in the absorption spectrum in the visible spectral region. The experiments were performed at different delay times <i>t</i><sub>1</sub> and <i>t</i><sub>2</sub>, which are the delays between UV-mid-IR and mid-IR-Vis pulses, respectively. Two sets of torsion-angle conformers were identified, one featuring a very fast mean ET time of 0.63 ps (group A) and another featuring a slower mean ET time of 4.3 ps (group B), in the absence of the mid-IR excitation. TD-DFT calculations were performed to determine key torsion angle dependent molecular parameters, including the electronic and vibrational transition dipoles, transition frequencies, and electronic couplings. To describe the 3-pulse data, we developed a kinetic model that includes a locally excited, acceptor-based S2 state, a charge separated S1 state, and their vibrationally excited counterparts, with either excited <i>ν</i><sub>CC</sub> (denoted as S1A<sup>tr</sup>, S1B<sup>tr</sup>, S2A<sup>tr</sup>, and S2B<sup>tr</sup>, where tr stands for the excited triplet bond, <i>ν</i><sub>CC</sub>) or excited daughter modes of the <i>ν</i><sub>CC</sub> relaxation (S1A<sup>h</sup>, S1B<sup>h</sup>, S2A<sup>h</sup>, and S2B<sup>h</sup>, where h stands for vibrationally hot species). The kinetic model was solved analytically, and the species-associated spectra (SAS) were determined numerically using a matrix approach, treating first the experiments with longer <i>t</i><sub>1</sub> delays and then using the already determined SAS for modeling the experiments with shorter <i>t</i><sub>1</sub> delays. Strong vibronic coupling of <i>ν</i><sub>CC</sub> and of vibrationally hot states makes the analysis complicated. Nevertheless, the SAS were identified and the ET rates of the vibrationally excited species, S2A<sup>tr</sup>, S2B<sup>tr</sup> and S2B<sup>h</sup>, were determined. The results show that the ET rate for the S2A species is <i>ca.</i> 1.2-fold slower when the <i>ν</i><sub>CC</sub> mode is excited. The ET rate for species S2B is slower by <i>ca.</i> 1.3-fold if the compound is vibrationally hot and is essentially unchanged when the <i>ν</i><sub>CC</sub> mode is excited. The SAS determined for the tr and h species resemble the SAS for their respective precursor species in the 2-pulse transient absorption experiments, which validates the procedure used and the results.}, Doi = {10.1039/d3cp03175f}, Key = {fds375216} } @article{fds375353, Author = {Dunlap-Shohl, WA and Tabassum, N and Zhang, P and Shiby, E and Beratan, DN and Waldeck, DH}, Title = {Electron-donating functional groups strengthen ligand-induced chiral imprinting on CsPbBr3 quantum dots.}, Journal = {Scientific reports}, Volume = {14}, Number = {1}, Pages = {336}, Year = {2024}, Month = {January}, url = {http://dx.doi.org/10.1038/s41598-023-50595-2}, Abstract = {Chiral perovskite nanoparticles and films are promising for integration in emerging spintronic and optoelectronic technologies, yet few design rules exist to guide the development of chiral material properties. The chemical space of potential building blocks for these nanostructures is vast, and the mechanisms through which organic ligands can impart chirality to the inorganic perovskite lattice are not well understood. In this work, we investigate how the properties of chiral ammonium ligands, the most common organic ligand type used with perovskites, affect the circular dichroism of strongly quantum confined CsPbBr<sub>3</sub> nanocrystals. We show that aromatic ammonium ligands with stronger electron-donating groups lead to higher-intensity circular dichroism associated with the lowest-energy excitonic transition of the perovskite nanocrystal. We argue that this behavior is best explained by a modulation of the exciton wavefunction overlap between the nanocrystal and the organic ligand, as the functional groups on the ligand can shift electron density toward the organic species-perovskite lattice interface to increase the imprinting.}, Doi = {10.1038/s41598-023-50595-2}, Key = {fds375353} } @article{fds375160, Author = {Pominova, M and Gabe, T}, Title = {Population size and the job matching of college graduates}, Journal = {Applied Economics Letters}, Volume = {30}, Number = {20}, Pages = {2994-2997}, Publisher = {Informa UK Limited}, Year = {2023}, Month = {November}, url = {http://dx.doi.org/10.1080/13504851.2022.2117774}, Doi = {10.1080/13504851.2022.2117774}, Key = {fds375160} } @article{fds371595, Author = {Sun, K and Fang, C and Kang, M and Zhang, Z and Zhang, P and Beratan, DN and Brown, KR and Kim, J}, Title = {Quantum Simulation of Polarized Light-Induced Electron Transfer with a Trapped-Ion Qutrit System.}, Journal = {The journal of physical chemistry letters}, Volume = {14}, Number = {26}, Pages = {6071-6077}, Year = {2023}, Month = {July}, url = {http://dx.doi.org/10.1021/acs.jpclett.3c01166}, Abstract = {Electron transfer within and between molecules is crucial in chemistry, biochemistry, and energy science. This study describes a quantum simulation method that explores the influence of light polarization on electron transfer between two molecules. By implementing precise and coherent control among the quantum states of trapped atomic ions, we can induce quantum dynamics that mimic the electron-transfer dynamics in molecules. We use three-level systems (qutrits), rather than traditional two-level systems (qubits), to enhance the simulation efficiency and realize high-fidelity simulations of electron-transfer dynamics. We treat the quantum interference between the electron coupling pathways from a donor with two degenerate excited states to an acceptor and analyze the transfer efficiency. We also examine the potential error sources that enter the quantum simulations. The trapped-ion systems have favorable scalings with system size compared to those of classical computers, promising access to richer electron-transfer simulations.}, Doi = {10.1021/acs.jpclett.3c01166}, Key = {fds371595} } @article{fds372766, Author = {de Soyres, F and Frohm, E and Highkin, E and Mix, C}, Title = {Forward Looking Exporters}, Journal = {International Finance Discussion Paper}, Number = {1377}, Pages = {1-18}, Publisher = {Board of Governors of the Federal Reserve System}, Year = {2023}, Month = {July}, url = {http://dx.doi.org/10.17016/ifdp.2023.1377}, Abstract = {<jats:p>This paper studies the role of expectations in driving export adjustment. We assemble bilateral data on spot exchange rates, one year ahead exchange rate forecasts and HS2-product export data for 11 exporting countries and 64 destinations, covering the 2006–2014 period. Results from fixed effects regressions and an instrumental variables approach show that expectations of exchange rate changes are an important channel for export adjustment. A one percent expected exchange rate depreciation over the next year is associated with a 0.96 percent increase in the extensive margin (entry of new exporters) in the 2SLS regression, with statistically insignificant effects on total exports or the intensive margin. We provide intuition for these findings with a simple model with heterogeneous firms and sticky prices, and use our model to discuss the implications of anticipation for subsequent export growth and trade elasticity measurement.</jats:p>}, Doi = {10.17016/ifdp.2023.1377}, Key = {fds372766} } @article{fds370446, Author = {Terai, K and Yuly, JL and Zhang, P and Beratan, DN}, Title = {Correlated particle transport enables biological free energy transduction.}, Journal = {Biophysical journal}, Volume = {122}, Number = {10}, Pages = {1762-1771}, Year = {2023}, Month = {May}, url = {http://dx.doi.org/10.1016/j.bpj.2023.04.009}, Abstract = {Studies of biological transport frequently neglect the explicit statistical correlations among particle site occupancies (i.e., they use a mean-field approximation). Neglecting correlations sometimes captures biological function, even for out-of-equilibrium and interacting systems. We show that neglecting correlations fails to describe free energy transduction, mistakenly predicting an abundance of slippage and energy dissipation, even for networks that are near reversible and lack interactions among particle sites. Interestingly, linear charge transport chains are well described without including correlations, even for networks that are driven and include site-site interactions typical of biological electron transfer chains. We examine three specific bioenergetic networks: a linear electron transfer chain (as found in bacterial nanowires), a near-reversible electron bifurcation network (as in complex III of respiration and other recently discovered structures), and a redox-coupled proton pump (as in complex IV of respiration).}, Doi = {10.1016/j.bpj.2023.04.009}, Key = {fds370446} } @book{fds370589, Author = {Liu, Y and Ji, J and Wu, G and Liang, M-M}, Title = {传承中文 Modern Chinese for Heritage Beginners Stories about Us}, Pages = {257 pages}, Publisher = {Taylor & Francis}, Year = {2023}, Month = {April}, ISBN = {9781000860344}, Abstract = {The book starts with talking about individuals and families and then expands to the Chinese and Asian American communities in the U.S. and eventually to the entire American society, all from the unique perspective of Chinese American ...}, Key = {fds370589} } @article{fds370590, Author = {Liu, Y}, Title = {Boundary Crossing: Integrating Visual Arts into Teaching Chinese as a Foreign Language}, Booktitle = {Crossing Boundaries in Researching, Understanding, and Improving Language Education: Essays in Honor of G. Richard Tucker.}, Publisher = {Springer}, Editor = {Zhang, D and Miller, R}, Year = {2023}, Month = {March}, ISBN = {978-3-031-24078-2}, Abstract = {This chapter reports on the author’s effort to cross disciplinary boundaries in teaching Chinese as a foreign language (CFL). It presents a mixed-methods study that examines student perceptions about, as well as the benefits and the challenges of, integrating visual arts and online art museum visits into CFL teaching. Quantitative and qualitative data were collected from a questionnaire and semi-structured interviews. Based on the findings, the author discusses the benefits of using art-integration approaches in CFL teaching, particularly their potential in answering the Modern Language Association’s call for curricular transformation in collegiate foreign language curriculum (MLA, Foreign languages and higher education: New structures for a changed world. Retrieved from http://www.mla.org/flreport, 2007). The author also analyzes the challenges encountered and proposes future research directions and suggestions for future integration of visual arts in the CFL curriculum.}, Key = {fds370590} } @article{fds371555, Author = {Bei, X}, Title = {Local Linearization Based Subvector Inference in Moment Inequality Models}, Year = {2023}, Month = {March}, Key = {fds371555} } @article{fds370591, Author = {Liu, Y}, Title = {Cross-language and cross-disciplinary collaborations in a Mandarin CLAC course}, Pages = {159-175}, Booktitle = {A Transdisciplinary Approach to Chinese and Japanese Language Teaching}, Publisher = {Routledge}, Year = {2023}, Month = {February}, url = {http://dx.doi.org/10.4324/9781003266976-15}, Doi = {10.4324/9781003266976-15}, Key = {fds370591} } | |
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