Filters








361 Hits in 8.1 sec

Improving the Performance of Tensor Matrix Vector Multiplication in Cumulative Reaction Probability Based Quantum Chemistry Codes [chapter]

Dinesh Kaushik, William Gropp, Michael Minkoff, Barry Smith
2008 Lecture Notes in Computer Science  
In this paper, we discuss the tensor product form of applying the system operator on a vector.  ...  For this reason, these codes use iterative methods to solve the linear systems, where a good fraction of the execution time is spent on matrix-vector multiplication.  ...  The computer time was supplied by DOE (through Argonne, NERSC, and ORNL) and NSF (through Teragrid at SDSC). This work was supported by the U.S. Dept. of Energy under Contract DE-AC02-06CH11357.  ... 
doi:10.1007/978-3-540-89894-8_14 fatcat:ggqwwjl7t5hjxmh2ncf7lnx7ii

Modern quantum chemistry with [Open]Molcas

Francesco Aquilante, Jochen Autschbach, Alberto Baiardi, Stefano Battaglia, Veniamin A. Borin, Liviu F. Chibotaru, Irene Conti, Luca De Vico, Mickaël Delcey, Ignacio Fdez. Galván, Nicolas Ferré, Leon Freitag (+27 others)
2020 Journal of Chemical Physics  
This article provides a comprehensive overview of the main features of the code, specifically reviewing the use of the code in previously reported chemical applications as well as more recent applications  ...  including the calculation of magnetic properties from optimized density matrix renormalization group wave functions.  ...  The list of quantum chemistry computer programs, maintained at Wikipedia, 1 contains almost one hundred different computational codes with a large overlap in the functionality.  ... 
doi:10.1063/5.0004835 pmid:32505150 fatcat:wusdvjinubgq3pa6hkuvuksffu

Accurate variational electronic structure calculations with the density matrix renormalization group [article]

Sebastian Wouters
2014 arXiv   pre-print
During the past 15 years, the density matrix renormalization group (DMRG) has become increasingly important for ab initio quantum chemistry.  ...  The underlying matrix product state (MPS) ansatz is a low-rank decomposition of the full configuration interaction tensor.  ...  For each contribution, two matrix-matrix multiplications need to be performed, of computational cost O(D 3 ).  ... 
arXiv:1405.1225v1 fatcat:vprkiy3kg5c3zc6dwoj7phdnru

Noisy intermediate-scale quantum (NISQ) algorithms [article]

Kishor Bharti, Alba Cervera-Lierta, Thi Ha Kyaw, Tobias Haug, Sumner Alperin-Lea, Abhinav Anand, Matthias Degroote, Hermanni Heimonen, Jakob S. Kottmann, Tim Menke, Wai-Keong Mok, Sukin Sim (+2 others)
2021 arXiv   pre-print
In the search for quantum advantage with these devices, algorithms have been proposed for applications in various disciplines spanning physics, machine learning, quantum chemistry and combinatorial optimization  ...  The goal of such algorithms is to leverage the limited available resources to perform classically challenging tasks.  ...  Adaptations of the UCC quantum chemistry ansatz, introduced in Sec.  ... 
arXiv:2101.08448v2 fatcat:eawbcaxikjeb7d3wqbjhutjdxy

Real-time prediction of 1H and 13C chemical shifts with DFT accuracy using a 3D graph neural network

Yanfei Guan, S. V. Shree Sowndarya, Liliana C. Gallegos, Peter C. St. John, Robert S. Paton
2021 Chemical Science  
Stereoisomers and conformers of organic molecules can be correctly distinguished.  ...  From quantum chemical and experimental NMR data, a 3D graph neural network, CASCADE, has been developed to predict carbon and proton chemical shifts.  ...  The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S.  ... 
doi:10.1039/d1sc03343c pmid:34667567 pmcid:PMC8457395 fatcat:dw6oul22pbetjn4b3kthy7z2zq

Analyzing Learned Molecular Representations for Property Prediction [article]

Kevin Yang, Kyle Swanson, Wengong Jin, Connor Coley, Philipp Eiden, Hua Gao, Angel Guzman-Perez, Timothy Hopper, Brian Kelley, Miriam Mathea, Andrew Palmer, Volker Settels, Tommi Jaakkola, Klavs Jensen (+1 others)
2019 arXiv   pre-print
Our empirical findings indicate that while approaches based on these representations have yet to reach the level of experimental reproducibility, our proposed model nevertheless offers significant improvements  ...  construct a learned molecular representation by operating on the graph structure of the molecule.  ...  While most datasets experience a moderate 2-5% improvement in performance following hyperparameter optimization, the quantum mechanics datasets (QM7, QM8, and QM9) and PCBA see dramatic improvements in  ... 
arXiv:1904.01561v5 fatcat:cwya5l23hfajrbl6z5ywrjsgly

Quantum computing enhanced machine learning for physico-chemical applications [article]

Manas Sajjan, Junxu Li, Raja Selvarajan, Shree Hari Sureshbabu, Sumit Suresh Kale, Rishabh Gupta, Sabre Kais
2021 arXiv   pre-print
In the recent years, it is safe to conclude that ML and its close cousin deep learning (DL) have ushered unprecedented developments in all areas of physical sciences especially chemistry.  ...  The objective of the review is to not only to foster exposition to the aforesaid techniques but also to empower and promote cross-pollination among future-research in all areas of chemistry which can benefit  ...  quantum matching machines. 213 The notion of self improvement of the performances of quantum machines via quantum learning was introduced by Ron Chrisley in 1995 in 214 through the example of barrier  ... 
arXiv:2111.00851v1 fatcat:i2caiglszvbufbyfmf3cwkcduu

Analyzing Learned Molecular Representations for Property Prediction

Kevin Yang, Kyle Swanson, Wengong Jin, Connor W. Coley, Philipp Eiden, Hua Gao, Angel Guzman-Perez, Tim Hopper, Brian Kelley, Miriam Mathea, Andrew Palmer, Volker Settels (+3 others)
2019 Journal of Chemical Information and Modeling  
Our empirical findings indicate that while approaches based on these representations have yet to reach the level of experimental reproducibility, our proposed model nevertheless offers significant improvements  ...  construct a learned molecular representation by operating on the graph structure of the molecule.  ...  Links to our code and to demonstration of our Web-based user interface, further comparisons of model performance on both scaffold-based and random splits of data, tables with all raw performance numbers  ... 
doi:10.1021/acs.jcim.9b00237 pmid:31361484 pmcid:PMC6727618 fatcat:lvudvf2wvzedfehqzova2gn4u4

Optimization of the linear-scaling local natural orbital CCSD(T) method: Redundancy-free triples correction using Laplace transform

Péter R. Nagy, Mihály Kállay
2017 Journal of Chemical Physics  
The success of the PNO based methods motivated the development of other MP2 NO based correlation orbitals, such as the orbital specific virtual (OSV) orbitals 102-105 of Manby and co-workers or the local  ...  An improved algorithm is presented for the evaluation of the (T) correction as a part of our local natural orbital (LNO) coupled-cluster singles and doubles with perturbative triples [LNO-CCSD(T)] scheme  ...  Scaling reduction ideas on the basis of denominator factorization, introduced first by Almlöf and Häser, [42] [43] [44] have also been successfully employed in multiple areas of quantum chemistry.  ... 
doi:10.1063/1.4984322 pmid:28576082 pmcid:PMC5453808 fatcat:nrxzfuptbnhztfuilva2ulbycm

Applications of coherent classical communication and the Schur transform to quantum information theory [article]

Aram W. Harrow
2005 arXiv   pre-print
This thesis contributes two new, purely quantum, tools to quantum information theory--coherent classical communication in the first half and an efficient quantum circuit for the Schur transform in the  ...  information over quantum channels or efficiently performing particular basis changes on a quantum computer.  ...  Performing an elementary quantum gate corresponds to multiplying this (length 2 n ) vector of amplitudes by a unitary matrix of size 2 n × 2 n .  ... 
arXiv:quant-ph/0512255v1 fatcat:4laqi2fizved5da25arvh2jj7e

A review of blind source separation in NMR spectroscopy

Ichrak Toumi, Stefano Caldarelli, Bruno Torrésani
2014 Progress in nuclear magnetic resonance spectroscopy  
In this review, we shall provide an historical overview of the application of Blind Source Separation methodologies to NMR , including methods specifically designed for the specificity of this spectroscopy  ...  With the revamp of NMR of complex mixtures, fueled by analytical challenges such as metabolomics, alternative and more apt mathematical methods for data processing have been sought, with the aim of decomposing  ...  Given a random 1 × n vector, the second order joint cumulants form an n × n matrix, and the fourth order joint cumulants form an n × n × n × n tensor (i.e. a 4 entries hypercubic Nicotinic acid, Ephedrine  ... 
doi:10.1016/j.pnmrs.2014.06.002 pmid:25142734 fatcat:vcqvsc4gr5ggbfczdrvpnwon7m

Quantum optimization using variational algorithms on near-term quantum devices

Nikolaj Moll, Panagiotis Barkoutsos, Lev S Bishop, Jerry M Chow, Andrew Cross, Daniel J Egger, Stefan Filipp, Andreas Fuhrer, Jay M Gambetta, Marc Ganzhorn, Abhinav Kandala, Antonio Mezzacapo (+6 others)
2018 Quantum Science and Technology  
In this context, the quantum volume as a metric to compare the power of near-term quantum devices is discussed.  ...  This variational approach can be used both for classical optimization problems as well as for problems in quantum chemistry.  ...  Extensions of the SPSA method that include approximations to the Hessian matrix can be explored to improve the speed of the optimization in the final steps, where estimating second derivatives helps achieve  ... 
doi:10.1088/2058-9565/aab822 fatcat:2noi4vqcazdqpblgvqlxjp3g5a

Machine Learning Force Fields [article]

Oliver T. Unke, Stefan Chmiela, Huziel E. Sauceda, Michael Gastegger, Igor Poltavsky, Kristof T. Schütt, Alexandre Tkatchenko, Klaus-Robert Müller
2021 arXiv   pre-print
In recent years, the use of Machine Learning (ML) in computational chemistry has enabled numerous advances previously out of reach due to the computational complexity of traditional electronic-structure  ...  One of the most promising applications is the construction of ML-based force fields (FFs), with the aim to narrow the gap between the accuracy of ab initio methods and the efficiency of classical FFs.  ...  When multiple quantum chemical codes (or even different versions of the same code) are used for data generation, it should be checked that their output is numerically identical when given the same input  ... 
arXiv:2010.07067v2 fatcat:shqhw36dibf2hgteim3xeywxxu

Machine Learning Force Fields

Oliver T. Unke, Stefan Chmiela, Huziel E. Sauceda, Michael Gastegger, Igor Poltavsky, Kristof T. Schütt, Alexandre Tkatchenko, Klaus-Robert Müller
2021 Chemical Reviews  
In recent years, the use of machine learning (ML) in computational chemistry has enabled numerous advances previously out of reach due to the computational complexity of traditional electronic-structure  ...  One of the most promising applications is the construction of ML-based force fields (FFs), with the aim to narrow the gap between the accuracy of ab initio methods and the efficiency of classical FFs.  ...  We would like to thank Stefan Ganscha for the valuable input to the manuscript.  ... 
doi:10.1021/acs.chemrev.0c01111 pmid:33705118 pmcid:PMC8391964 fatcat:7zssmfreg5alnnrjcwvh4hipk4

Continuing challenges in the parametrization of intermolecular force fields. Towards an accurate description of electrostatic and induction terms

Christophe Chipot, János G. Ángyán
2005 New Journal of Chemistry  
Christophe Chipot received his BSc and MSc in physical chemistry from the University Henri Poincare´in Nancy, France.  ...  The improvement in the description of molecular liquids by statistical mechanics simulations, going beyond the limitations of the pairwise additive approximation, has triggered the development of novel  ...  The Centre Charles Hermite (CRVHP; Vandaeuvre-le`s-Nancy, France) and the CINES (Montpellier, France) are gratefully acknowledged for provision of generous amounts of CPU time on their SGI Origin 3000  ... 
doi:10.1039/b414280m fatcat:mstf6njs5nfpfhllgm72pyiz6a
« Previous Showing results 1 — 15 out of 361 results