197,655 research outputs found
Full-Dimensional Ammonia Vibrational Spectrum from a Handful of Classical Trajectories
No full textThe accurate description of quantum properties in real molecules is a major computational task, due to the growing efforts required as the number of degrees of freedom of the system increases.
Different semiclassical methods have been adopted in the attempt to gather quantum properties from computationally cheap classical-trajectories simulations. However, issues related to possible chaotic behavior and classical integrator instability at long simulation times, together with large number of classical trajectories required often to limit the success of basic semiclassical approaches to model systems.
In the present work, we demonstrate that the multidimensional double well full vibrational spectrum, including tunnel splitting, can be described quite accurately by generating only 8 classical trajectories if Multi Coherent States Time Averaging SemiClassical Initial Value Representation (MC-TA-SCIVR) is used.[1-4] The first promising results have been obtained on a 1D double-well potential aimed at describing the umbrella motion in ammonia;[5] then, the full-dimensional vibrational spectrum of ammonia is presented, computed on both a high-level fitted PES [6,7] and ab-initio on-the-fly simulations.
For the first time in classical-trajectories based methods, both tunnel splitting amplitudes and quantum vibrational frequencies are simultaneously reported.[8,9] Moreover, the exiguous number of trajectories needed makes the present approach reliable for ab-initio on-the-fly approaches, thus avoiding the request for multidimensional PES calculations.[9]
References
[1] M. Ceotto, S. Atahan, G.F. Tantardini and A. Aspuru-Guzik, Multiple coherent states for first-principles semiclassical initial value
representation molecular dynamics, J. Chem. Phys. 130, 234113 (2009).
[2] M. Ceotto, S. Atahan, S. Shim, G.F. Tantardini and A. Aspuru-Guzik, First-principles initial value represenation molecular dynamics, PCCP 11, 3861 (2009).
[3] M. Ceotto, G.F. Tantardini and A. Aspuru-Guzik, Fighting the curse of dimensionality in first-principles semiclassical calculations: non-local reference states for large number of dimensions, J. Chem. Phys. 135, 214108 (2011).
[4] A.L. Kaledin and W.H. Miller, Time averaging the semiclassical initial value representation for the calculation of vibrational energy levels, J. Chem. Phys. 118, 7174 (2003).
[5] C.-K. Lin, H.-C. Chang and S.H. Lin, Symmetric Double-Well Potential Model and Its Application to Vibronic Spectra:Studies of
InversionModes of Ammonia and Nitrogen-Vacancy Defect Centers in Diamond, J. Phys. Chem. A 111, 9347 (2007).
[6] J.M.L. Martin and T.J. Lee, An Accurate ab Initio Quartic Force Field for Formaldehyde and Its Isotopomers, J. Mol. Spect. 160, 105
(1993).
[7] N.C. Handy, S. Carter and S.M. Colwell, The vibrational levels of ammonia, Mol. Phys. 96, 477 (1999).
[8] A.L. Kaledin and W.H. Miller, TA-SCIVR for vibrational levels. Application to H2CO, NH3, CH4, CH2D2, J. Chem. Phys. 119, 3078 (2003).
[9] R. Conte, A. Aspuru-Guzik and M. Ceotto, Full-dimensional ammonia vibrational spectrum from a handful of classical trajectories, in progress
A few remarks on the impact of the framework decisions of the European Union Council on criminal legislation in Poland
No full textThe paper identifi es the areas of substantive, procedural as well as executive
criminal law, the areas most infl uenced by the European Union through framework
decisions. Much attention was devoted to the legitimization of framework decisions
within the system of sources of criminal law.Emil W. Pływaczewski - Uniwersytet w BiałymstokuEwa M. Guzik-Makaruk - Uniwersytet w Białymstok
Duch racjonalnego prawodawcy w obowiązującym kodeksie karnym
No full textZdigitalizowano i udostępniono w ramach projektu pn. Rozbudowa otwartych zasobów naukowych Repozytorium Uniwersytetu w Białymstoku, dofinansowanego z programu „Społeczna odpowiedzialność nauki” Ministra Edukacji i Nauki na podstawie umowy SONB/SP/512497/2021Ewa M. Guzik-Makaruk - Uniwersytet w BiałymstokuEmil W. Pływaczewski - Uniwersytet w Białymstoku27128
Dziecko, nieletni, małoletni, młodociany, pełnoletni - podstawowe zagadnienia terminologiczne na tle systemu prawa
No full textZdigitalizowano i udostępniono w ramach projektu pn. Rozbudowa otwartych zasobów naukowych Repozytorium Uniwersytetu w Białymstoku, dofinansowanego z programu „Społeczna odpowiedzialność nauki” Ministra Edukacji i Nauki na podstawie umowy SONB/SP/512497/2021Ewa M. Guzik-Makaruk - Wydział Prawa, Uniwersytet w BiałymstokuEwelina Wojewoda - Wydział Prawa, Uniwersytet w Białymstoku294
Racjonalny ustawodawca a racjonalne sądownictwo konstytucyjne na tle tzw. ubojów rytualnych w Polsce
No full textZdigitalizowano i udostępniono w ramach projektu pn. Rozbudowa otwartych zasobów naukowych Repozytorium Uniwersytetu w Białymstoku – kontynuacja, dofinansowanego z programu „Społeczna odpowiedzialność nauki” Ministra Edukacji i Nauki na podstawie umowy BIBL/SP/0040/2023/01.Emil W. Pływaczewski - Uniwersytet w BiałymstokuEwa M. Guzik-Makaruk - Uniwersytet w Białymstoku39340
Racjonalny ustawodawca w polskim prawie karnym – rozważania w związku z ustawą z dnia 13 maja 2016 r. o przeciwdziałaniu zagrożeniom przestępczością na tle seksualnym
No full textZdigitalizowano i udostępniono w ramach projektu pn. Rozbudowa otwartych zasobów naukowych Repozytorium Uniwersytetu w Białymstoku – kontynuacja, dofinansowanego z programu „Społeczna odpowiedzialność nauki” Ministra Edukacji i Nauki na podstawie umowy BIBL/SP/0040/2023/01.Ewa M. Guzik-Makaruk - Wydział Prawa, Uniwersytet w BiałymstokuEmil W. Pływaczewski - Wydział Prawa, Uniwersytet w Białymstoku76978
A General Purpose Implementations of Semiclassical Molecular Dynamics for CPU and GPU hardware
No full textThe calculation of the semiclassical propagator is a Monte Carlo integration over classical trajectories. This can be accelerated either by importance sampling or by parallelization of the phase space integration. In the first case, a multiple coherent states time-averaging [1] semiclassical initial value representation (MC-TA-SC-IVR) method for spectra calculations is presented.[2, 3] The method is implemented for ab initio semiclassical simulations, i.e. a direct dynamics approach, and it is shown to faithfully reproduce all kind of quantum effects, including ZPEs, anharmonicities, tunneling splittings,[4] resonances [5] and vibrational eigenfunctions.[6] This on-the-fly approach is useful in particular for complex systems,[7, 8] where the elaboration of a pre-computed potential energy surface can turn into a formidable task. In the second case, SC-IVR is implemented for GPUs hardware. [9] An almost constant scaling for GPU calculations versus a linear scaling for CPU ones is found respect to the number of trajectories. Issues and limitations related to the GPU implementation will be discussed.
[1] A. L. Kaledin and W. H. Miller, J. Chem. Phys. 118, 7174 (2003)
[2] M. Ceotto, S. Atahan, S. Shim, G. F. Tantardini, and A. Aspuru-Guzik, Phys. Chem. Chem. Phys. 11, 3861 (2009)
[3] M. Ceotto, S. Atahan, G. F. Tantardini, and A. Aspuru-Guzik, J. Chem. Phys. 130, 234113 (2009)
[4] R. Conte, A. Aspuru-Guzik, and M. Ceotto, J. Phys. Chem. Lett. 4, 3407-3412 (2013)
[5] M. Ceotto, D. Dell'Angelo, and G. F. Tantardini, J. Chem. Phys. 133, 054701 (2010)
[6] M. Ceotto, S. Valleau, G. F. Tantardini, and A. Aspuru-Guzik, J. Chem Phys. 134, 234103 (2011)
[7] M. Ceotto, G. F. Tantardini, and A. Aspuru-Guzik, J. Chem. Phys. 135, 214108 (2011)
[8] M. Ceotto, Y. Zhuang, and W.L. Hase, J. Chem. Phys. 138, 054116 (2013)
[9] D. Tamascelli, F. D'Ambrosio, R. Conte, and M. Ceotto, in progres
Offences Against Elections and Referenda – Selected Legal, Criminal and Criminological Aspects
No full textCreation of the English-language versions of the articles published in the „Białostockie Studia Prawnicze” [Białystok Legal Studies] funded under the contract no. 548/P-DUN/2016 and 548/1/P-DUN/2016 from resources of the Minister of Science and Higher Education dedicated to the popularisation of science.This research paper elaborates on the problem of offences against elections and referenda, and analyses provisions of the XXXI Chapter of the Polish Penal Code, penalizing electoral off ences. A detailed description of particular acts prohibited by law has been provided. Moreover, attention is given to issues causing interpreting problems. The paper presents a statistical overview of the occurrence of offences on the basis of data concerning initiated proceedings, and convictions by fi naljudgments.Ewa M. Guzik-Makaruk: [email protected] Wojewoda: [email protected] M. Guzik-Makaruk - University of BiałystokEwelina Wojewoda - University of BiałystokBudyn-Kulik M., Komentarz do rozdziału XXXI k.k., (in:) M. Mozgawa (ed.), M. Budyn-Kulik, P. Kozłowska-Kalisz, M. Kulik, Kodeks Karny. Komentarz, Warszawa 2012Hołyst B., Kryminologia, Warszawa 1994Jachimowicz M., Przestępstwo naruszenia swobody głosowania (art. 250 k.k.), Prokurator 2009, Nr 1 Kowalski S., Karnoprawna ochrona wykazu podpisów wyborców w wyborach samorządowych, Prok. i Pr. 2014, Nr 9Kozielewicz W., Rozdział IX. Przestępstwa przeciwko wyborom i referendum (in:) L. Gardocki (ed.), System Prawa Karnego. Przestępstwa przeciwko państwu i dobrom zbiorowym, t.8, Warszawa 2012Łabuda G., Komentarz do art. 248 k.k., (in:) J. Giezek (ed.), Kodeks karny. Część szczególna. Komentarz, Warszawa 2014Marek A., Kodeks Karny. Komentarz, Warszawa 2010Piskorski J., Przestępstwa przeciwko wyborom i referendum, (in:) M. Królikowski, R. Zawłocki (ed.), Kodeks Karny. Część Szczególna. Komentarz do art. 222-316, Warszawa 2013Skorupka J., Podstawy karania korupcji w kodeksie karnym de lege lata i de lege ferenda (wybrane zagadnienia), PiP 2003, nr 12Szewczyk M., Przestępstwa przeciwko wyborom i referendum, (in:) A. Zoll (ed.), Kodeks Karny. Komentarz do art. 117-277 k.k., Warszawa 2013Tyszkiewicz L., Przestępstwa przeciwko wyborom i referendum, (in:) M. Filar (ed.), Kodeks Karny. Komentarz, Warszawa 201220/A en15317
Ab initio direct semiclassical molecular dynamics
No full textA multiple coherent states time-averaging [1] semiclassical initial value representation (MC-TA-SC-IVR) method for spectra calculations is presented.[2, 3] The method is implemented for ab initio semiclassical simulations, i.e. a direct dynamics approach, and it is shown to faithfully reproduce all kind of quantum effects, including ZPEs, anharmonicities, tunneling splittings, resonances [4] and vibrational eigenfunctions.[5] This on-the-fly approach is useful in particular for complex systems,[5, 6] where the elaboration of a pre-computed potential energy surface can turn into a formidable task. I will show that the method can deal with molecules with multiple wells and as complex as glycine.
[1] A. L. Kaledin and W. H. Miller, J. Chem. Phys. 118, 7174 (2003)
[2] M. Ceotto, S. Atahan, S. Shim, G. F. Tantardini, and A. Aspuru-Guzik, Phys. Chem. Chem. Phys. 11, 3861 (2009)
[3] M. Ceotto, S. Atahan, G. F. Tantardini, and A. Aspuru-Guzik, J. Chem. Phys. 130, 234113 (2009)
[4] M. Ceotto, D. Dell'Angelo, and G. F. Tantardini, J. Chem. Phys. 133, 054701 (2010)
[5] M. Ceotto, S. Valleau, G. F. Tantardini, and A. Aspuru-Guzik, J. Chem Phys. 134, 234103 (2011)
[6] M. Ceotto, G. F. Tantardini, and A. Aspuru-Guzik, J. Chem. Phys. 135, 214108 (2011)
[7] M. Ceotto, Y. Zhuang, and W.L. Hase, J. Chem. Phys. 138, 054116 (2013
A multi-site variational master equation approach to dissipative energy transfer
No full textUnitary transformations can allow one to study open quantum systems in situations for which standard, weak-coupling type approximations are not valid. We develop here an extension of the variational (polaron) transformation approach to open system dynamics, which applies to arbitrarily large exciton transport networks with local environments. After deriving a time-local master equation in the transformed frame, we go on to compare the population dynamics predicted using our technique with other established master equations. The variational frame dynamics are found to agree with both weak coupling and full polaron master equations in their respective regions of validity. In parameter regimes considered difficult for these methods, the dynamics predicted by our technique are found to interpolate between the two. The variational method thus gives insight, across a broad range of parameters, into the competition between coherent and incoherent processes in determining the dynamical behaviour of energy transfer networks.Peer reviewe
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