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1. Basis set convergence of post-CCSD contributions to molecular atomization energies

Author

Karton, Amir, Taylor, Peter R., and Martin, Jan M. L.

Subjects
Physics - Chemical Physics
Abstract

Basis set convergence of correlation effects on molecular atomization energies beyond the CCSD (coupled cluster with singles and doubles) approximation has been studied near the one-particle basis set limit. Quasiperturbative connected triple excitations, (T), converge more rapidly than $L^{-3}$ (where $L$ is the highest angular momentum represented in the basis set), while higher-order connected triples, $T_3-(T)$, converge more slowly -- empirically, $\propto L^{-5/2}$. Quasiperturbative connected quadruple excitations, (Q), converge smoothly as $\propto L^{-3}$ starting with the cc-pVTZ basis set, while the cc-pVDZ basis set causes overshooting of the contribution in highly polar systems. Higher-order connected quadruples display only weak, but somewhat erratic, basis set dependence. Connected quintuple excitations converge very rapidly with the basis set, to the point where even an unpolarized double-zeta basis set yields useful numbers. In cases where fully iterative CCSDTQ5 (coupled cluster up to connected quintuples) calculations are not an option, CCSDTQ(5) (i.e., coupled cluster up to connected quadruples plus a quasiperturbative connected quintuples correction) cannot be relied upon in the presence of significant nondynamical correlation, whereas CCSDTQ(5)$_\Lambda$ represents a viable alternative. Connected quadruples corrections to the core-valence contribution are thermochemically significant in some systems. [...] We conclude that ``$3\sigma\leq 1$ kJ/mol'' thermochemistry is feasible with current technology, but that the more ambitious goal of $\pm$10 cm$^{-1}$ accuracy is illusory, at least for atomization energies., Comment: (J. Chem. Phys., in press)

Published
2007
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2. A definitive heat of vaporization of silicon through benchmark ab initio calculations on SiF_4

Author

Martin, Jan M. L. and Taylor, Peter R.

Subjects
Physics - Chemical Physics
Abstract

In order to resolve a significant uncertainty in the heat of vaporization of silicon -- a fundamental parameter in gas-phase thermochemistry -- $\Delta H^\circ_{f,0}$[Si(g)] has been determined from a thermochemical cycle involving the precisely known experimental heats of formation of SiF_4(g) and F(g) and a benchmark calculation of the total atomization energy (TAE_0) of SiF_4 using coupled-cluster methods. Basis sets up to $[8s7p6d4f2g1h]$ on Si and $[7s6p5d4f3g2h]$ on F have been employed, and extrapolations for residual basis set incompleteness applied. The contributions of inner-shell correlation (-0.08 kcal/mol), scalar relativistic effects (-1.88 kcal/mol), atomic spin-orbit splitting (-1.97 kcal/mol), and anharmonicity in the zero-point energy (+0.04 kcal/mol) have all been explicitly accounted for. Our benchmark TAE_0=565.89 \pm 0.22 kcal/mol leads to $\Delta H^\circ_{f,0}$[Si(g)]=107.15 \pm 0.38 kcal/mol ($\Delta H^\circ_{f,298}$[Si(g)]=108.19 \pm 0.38 kcal/mol): between the JANAF/CODATA value of 106.5 \pm 1.9 kcal/mol and the revised value proposed by Grev and Schaefer [J. Chem. Phys. 97, 8389 (1992}], 108.1 \pm 0.5 kcal/mol. The revision will be relevant for future computational studies on heats of formation of silicon compounds., Comment: J. Phys. Chem. A, submitted Feb 1, 1999

Published
1999
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3. Benchmark ab initio thermochemistry of the isomers of diimide, N_2H_2, using accurate computed structures and anharmonic force fields

Author

Martin, Jan M. L. and Taylor, Peter R.

Subjects
Physics - Chemical Physics
Abstract

A benchmark ab initio study on the thermochemistry of the trans-HNNH, cis-HNNH, and H$_2$NN isomers of diazene has been carried out using the CCSD(T) coupled cluster method, basis sets as large as $[7s6p5d4f3g2h/5s4p3d2f1g]$, and extrapolations towards the 1-particle basis set limit. The effects on inner-shell correlation and of anharmonicity in the zero-point energy were taken into account: accurate geometries and anharmonic force fields were thus obtained as by-products. Our best computed $\Delta H^\circ_{f,0}$ for trans-HNNH, 49.2 \pm 0.3 kcal/mol, is in very good agreement with a recent experimental lower limit of 48.8 \pm 0.5 kcal/mol. CCSD(T) basis set limit values for the isomerization energies at 0 K are 5.2 \pm 0.2 kcal/mol (cis-trans) and 24.1 \pm 0.2 kcal/mol (iso-trans). Our best computed geometry for trans-HNNH, $r_e$(NN)=1.2468 \AA, $r_e$(NH)=1.0283 \AA, and $\theta_e$=106.17$^\circ$, reproduces the precisely known ground-state rotational constants of trans-HNNH to within better than 0.1 %. The rotation-vibration spectra of both cis-HNNH and H$_2$NN are dominated by very strong Coriolis and Fermi resonances. In addition, the NH stretches in H$_2$NN are so strongly anharmonic that vibrational perturbation theory breaks down, and the molecule appears to be an excellent test case for variational treatments of the vibrational Schr\"odinger equation., Comment: RevTeX, 30 pages; for B. Liu memorial issue of Molecular Physics

Published
1998
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4. C20: Fulleren, Bowl or Ring? New Results from Coupled-Cluster Calculations

Author

Taylor, Peter R., Bylaska, Eric, Weare, John H., and Kawai, Ryoichi

Subjects
Physics - Chemical Physics
Abstract

Contrary to recent experimental evidence suggesting that the monocyclic ring is the most stable 20-atom carbon species, highly accurate calculations convincingly predict that the smallest fullerene, the dodecahedron C$_{20}$, has the lowest energy. A related corannulene-like bowl is nearly degenerate in energy to the fullerene. Thermodynamic considerations suggest that at formation temperatures of around 700 K the bowl should be the dominant species. The recent application of gradient corrections to LDA which supported the ring structure is qualitatively in error. (RK-94-02), Comment: 4 pages. one postscript figure included. Revtex and psfig. A complete postscript file including figures is availabel via anonymous ftp at ftp://ftp.phy.uab.edu/pub/publications/kawai/RK-94-02.ps

Published
1994
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15. Calculations of the absorption spectrum of chromone

Author

Polly, Robert and Taylor, Peter R.

Subjects
Density functionals -- Usage, Molecules -- Research, Chemicals, plastics and rubber industries
Abstract

A theoretical study of the optical characteristics of the chromone molecule using multireference perturbation theory and density functional theory, is presented.

Published
1999

16. Boron heat of formation revisited: relativistic effects of the BF3 atomization energy

Author

Bauschlicher, Charles W., Jr., Martin, Jan M.L., and Taylor, Peter R.

Subjects
Atomization -- Research, Boron -- Research, Chemicals, plastics and rubber industries
Abstract

It has been possible to compute the scalar relativistic contribution to the atomization energies of BF3. Scalar relativistic effects cut the atomization energy of BF3 by around 0.7 kcal/mol.

Published
1999

17. A definitive heat of vaporization of silicon through benchmark ab initio calculations on SiF4

Author

Martin, Jan M.L. and Taylor, Peter R.

Subjects
Vaporization, Heats of -- Research, Silicon compounds -- Research, Atomization -- Research, Chemicals, plastics and rubber industries
Abstract

Research was conducted to address questions on the heat of vaporization of silicon through a benchmark calculation of the total atomization energy of SiF4 molecule. Results supported the suggestion of Grev and Schaefer that the uncertain JANAF/CODATA value of 106.5+1-1.9 kcal/mol must be revised to a lower value. Future studies on heats produced by silicon compound formation could take advantage of the revision.

Published
1999

20. Revised heat of formation for gaseous boron: basis set limit ab initio binding energies of BF3 and BF

Author

Martin, Jan M.L. and Taylor, Peter R.

Subjects
Boron -- Analysis, Binding energy -- Analysis, Chemicals, plastics and rubber industries
Abstract

The total atomization energy of BF3 was accurately obtained ab initio in a comprehensive study employing coupled cluster techniques to compute the heat of formation of boron atom. Basis sets up to (8s7p6df4g3h2i) quality were analyzed and an extrapolation for further basis set incompleteness was used. Inner-shell correlation, anharmonicity in the zero-point energy and atomic spin-orbit splitting were all considered. The best heat of formation for gaseous boron at 0 K was 136.0 kcal/mol.

Published
1998

23. The Dalton quantum chemistry program system

Author

Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pal, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenæs, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjærgaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnæs, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., Sanchez de Merás, Alfredo, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, Ågren, Hans, Aidas, Kestuti, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linu, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thoma, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenæs, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa, Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjærgaard, Thoma, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andrea, Kristensen, Kasper, Ligabue, Andrea, Lutnæs, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Ander, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvina, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, Ågren, Hans, Dipartimento di Chimica, Università degli Studi di Ferrara (UniFE), Centre for Theoretical and Computational Chemistry [Oslo] (CTCC), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Groupe Méthodes et outils de la chimie quantique (LCPQ) (GMO), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Department of Physics, Chemistry and Biology, Amsterdam Center for Multiscale Modeling, Vrije Universiteit Amsterdam [Amsterdam] (VU), Laboratory of the Department of Oncology (DEPARTMENT OF ONCOLOGY), Herlev and Gentofte Hospital, Norwegian Meteorological Institute [Oslo] (MET), Teoretisk Kemi, Aarhus University [Aarhus], Centre for Biodiversity Dynamics, Norwegian University of Science and Technology [Trondheim] (NTNU), Norwegian University of Science and Technology (NTNU)-Norwegian University of Science and Technology (NTNU), Karlsruhe Institute of Technology (KIT), Department of Theoretical Chemistry, University Düsseldorf, Department of Mathematics, Tokyo University of Science, Institut Jean-Pierre Bourgin (IJPB), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Department of Environmental Engineering, Technical University of Denmark [Lyngby] (DTU), Computer Services Networks and Systems, Università degli Studi di Modena e Reggio Emilia (UNIMORE), Hammersmith Hospital, Imperial College, London, Department of Haematology, Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Centre d'études biologiques de Chizé (CEBC), Centre National de la Recherche Scientifique (CNRS), Centre for Theoretical and Computational Chemistry, University of Tromsø (UiT), Department of Electronics Materials and Devices, Ivanovo State University of Chemistry and Technology, Department of Chemistry [Copenhagen], Institut für Nukleare Entsorgung (INE), Karlsruher Institut für Technologie (KIT), Department of Pharmacology, Skaggs School of Pharmacy & Pharmaceutical Sciences, University of California [San Diego] (UC San Diego), University of California-University of California, School of Chemistry, University of Nottingham, UK (UON), Theoretical Chemistry, Royal Institute of Technology [Stockholm] (KTH ), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Norwegian Meteorological Institute, Bakke, Vebjørn, Hjertenaes, Eirik, Høyvik, Ida Marie, Jensen, Hans Jørgen A. a., Kjaergaard, Thoma, Lutnaes, Ola B., Sánchez de Merás, Alfredo, Sylvester Hvid, Kristian O., Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
Materials Chemistry2506 Metals and Alloys, Software Focus, Ab initio electronic structure methods structure methods, ab initio calculations, VDP::Mathematics and natural science: 400::Chemistry: 440::Theoretical chemistry, quantum chemistry: 444, Computer Science Applications1707 Computer Vision and Pattern Recognition, Quantum chemistry program, Ab-initio methods, Scientific Software, Quantum Chemistry, Molecular properties, Biochemistry, Algorithms, [Electronic Structure Theory], Algorithm, Molecular propertie, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Computational Chemistry, Computational Mathematic, Faculty of Science, Physical and Theoretical Chemistry, VDP::Matematikk og Naturvitenskap: 400::Kjemi: 440::Teoretisk kjemi, kvantekjemi: 444
Abstract

Dalton is a powerful general-purpose program system for the study of molecular electronic structure at the Hartree–Fock, Kohn–Sham, multiconfigurational self-consistent-field, Møller–Plesset, configuration-interaction, and coupled-cluster levels of theory. Apart from the total energy, a wide variety of molecular properties may be calculated using these electronic-structure models. Molecular gradients and Hessians are available for geometry optimizations, molecular dynamics, and vibrational studies, whereas magnetic resonance and optical activity can be studied in a gauge-origin-invariant manner. Frequency-dependent molecular properties can be calculated using linear, quadratic, and cubic response theory. A large number of singlet and triplet perturbation operators are available for the study of one-, two-, and three-photon processes. Environmental effects may be included using various dielectric-medium and quantum-mechanics/molecular-mechanics models. Large molecules may be studied using linear-scaling and massively parallel algorithms. Dalton is distributed at no cost from http://www.daltonprogram.org for a number of UNIX platforms. © 2013 John Wiley & Sons, Ltd. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, (CC BY-NC-ND 3.0)

Published
2014

24. Configurations of equivalent electrons

Author

Taylor, Peter R.

Subjects
Angular momentum -- Analysis, Spin coupling -- Analysis, Wave functions -- Analysis, Chemicals, plastics and rubber industries
Published
2009

26. Motivating Your Team : Coaching for Performance in Schools Ed. 1

Author

Taylor, Peter R., Taylor, Peter R., Taylor, Peter R., and Taylor, Peter R.

Abstract

'Motivating Your Team is an excellent handbook for all those who intend to get the best out to their team, to motivate, lead and support individuals as well as groups of people, and thus assist them in maximizing their performance as professionals?.[It] is an excellent resource I would like to recommend wholeheartedly to all those who are involved in appraisal processes in whatever capacity' - Educational Management Administration and Leadership 'Taylor has produced a book which goes to the theoretical and practical heart of coaching in modern school leadership' - Management in Education 'Each page arrives crisp and clear underpinned by a transparent rationale... A useful addition on the book shelf of head teachers and school leadership programmes' - ESCalate Designed to help you get the best out of your team, this practical book shows you how to motivate and engage people through the effective design, application and review of performance management. Checklists and practical guidance notes are provided to help you understand the principles and practice of effective performance management and how the process can be an essential lever in enhancing the performance and motivation of individuals and teams in your organization. Headteachers, team leaders, governors and trainers will reach for this book again and again.

Published
2007

27. The Dalton quantum chemistry program system

Author

Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dalskov, Erik K., Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Iozzi, Maria Francesca, Jonsson, Dan, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sa?ek, Pawel, Samson, Claire C. M., Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Vahtras, Olav, Watson, Mark A., Wilson, David J. D., and Ziolkowski, Marcin

Published
2013

28. Endovascular treatment of acute aortic syndrome

Author

Clough, Rachel E, Mani, Kevin, Lyons, Oliver T, Bell, Rachel E, Zayed, Hany A, Waltham, Matthew, Carrell, Tom W, Taylor, Peter R, Clough, Rachel E, Mani, Kevin, Lyons, Oliver T, Bell, Rachel E, Zayed, Hany A, Waltham, Matthew, Carrell, Tom W, and Taylor, Peter R

Abstract

BACKGROUND: The term acute aortic syndrome (AAS) encompasses a range of conditions that have a risk of imminent aortic rupture and where delays in treatment result in increased mortality. Endovascular treatment offers an attractive alternative to open surgery but little is known about the durability of the repair and the factors that predict mortality. METHODS: Prospective data were collected for a cohort of 110 consecutive patients with endovascular treatment for AAS. Patient and procedural characteristics were related to short- and midterm outcome using multivariate logistic regression analysis. RESULTS: There were 75 men and 35 women with a median age of 68 (range 57-76) years. The pathologies treated were acute dissection (35), symptomatic aneurysm (32), infected aneurysm (18), transection (12), chronic dissection (9), penetrating ulcer (3), and intramural hematoma (1). Thirty-day mortality was 12.7% and this was associated with hypotension (odds ratio [OR], 5.25), use of general anesthetic (OR, 5.23), long procedure duration (OR, 2.03), and increasing age (OR, 1.07). The causes of death were aortic rupture (4), myocardial infarction (4), stroke (3), and multisystem organ failure (3). The stroke and paraplegia rates were 7.3% and 6.4%, respectively. The 1-year survival was 81% and the 5-year survival 63%. Secondary procedures were required in 13 (11.8%) patients. Factors associated with death at 1 year were presence of an aortic fistula (OR, 9.78), perioperative stroke (OR, 5.87), and use of general anesthetic (OR, 3.76); and at 5 years were aortic fistula (OR, 12.31) and increasing age (OR, 1.06). CONCLUSIONS: Acute aortic syndrome carries significant early and late mortality. Emergency endovascular repair offers a minimally invasive treatment option associated with acceptable short and midterm results. Continued surveillance is important as secondary procedures and aortic-related deaths continue to occur throughout the follow-up period.

Published
2011
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29. On the behaviour of the Hartree-Fock energy at short internuclear distances

Author

Gilka, Natalie, Solovej, Jan Philip, Taylor, Peter R., Gilka, Natalie, Solovej, Jan Philip, and Taylor, Peter R.

Abstract

There are well-established mathematical relationships for the energy of a diatomic molecule (the exact energy, but also both the Hartree-Fock and Thomas-Fermi energies) in the limit of large nuclear charge of the atoms and small internuclear distances. We present calculated energies for a number of homonuclear diatomic molecules at short internuclear distances for numerical comparison with these established relationships. Intriguingly, they hold in practice for relatively small nuclear charges and for relatively long internuclear distances.

Published
2011

30. Accurate quantum-chemical calculations using Gaussian-type geminal and Gaussian-type orbital basis sets : applications to atoms and diatomics

Author

Dahle, Pal, Helgaker, Trygve, Jonsson, Dan, Taylor, Peter R., Dahle, Pal, Helgaker, Trygve, Jonsson, Dan, and Taylor, Peter R.

Abstract

We have implemented the use of mixed basis sets of Gaussian one- and two-electron (geminal) functions for the calculation of second-order Moller-Plesset (MP2) correlation energies. In this paper, we describe some aspects of this implementation, including different forms chosen for the pair functions. Computational results are presented for some closed-shell atoms and diatomics. Our calculations indicate that the method presented is capable of yielding highly accurate second-order correlation energies with rather modest Gaussian orbital basis sets, providing an alternative route to highly accurate wave functions. For the neon atom, the hydrogen molecule, and the hydrogen fluoride molecule, our calculations yield the most accurate MP2 energies published so far. A critical comparison is made with established MP2-R12 methods, revealing an erratic behaviour of some of these methods, even in large basis sets., authorCount :4

Published
2007
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36. Ab initio calibration study of the heat of formation, geometry, and anharmonic force field of fluoroacetylene

Author

Persoon, B. Joakim, Taylor, Peter R., and Martin, Jan M.L.

Subjects
Fluorine compounds -- Analysis, Acetylene -- Analysis, Chemicals, plastics and rubber industries
Abstract

The full quartic force field, heat of formation, geometry and harmonic frequencies of fluoroacetylene (FCCH) are examined using coupled cluster methods with basis sets. It is shown that FCCH fundamentals can be reproduced to about 2/cm and the rotational constants to four decimal places without empirical correction. The best computed geometry, harmonic frequencies and heat of formation are discussed.

Published
1998

39. Highly Accurate Quartic Force Fields, Vibrational Frequencies, and Spectroscopic Constants for Cyclic and Linear C3H3+.

Author

Huang, Xinchuan, Taylor, Peter R., and Lee, Timothy J.

Subjects
*CATIONS, *QUANTUM perturbations, *EXTRAPOLATION, *DISSOCIATION (Chemistry), *FORCING (Model theory)
Abstract

High levels of theory have been used to compute quartic force fields (QFFs) for the cyclic and linear forms of the C3H3+ molecular cation, referred to as c-C3H3+ and 1-C3H3+. Specifically, the singles and doubles coupled-cluster method that includes a perturbation a! estimate of connected triple excitations, CCSD(T), has been used in conjunction with extrapolation to the one-particle basis set limit, and corrections for scalar relativity and core correlation have been included. The QFFs have been used to compute highly accurate fundamental vibrational frequencies and other spectroscopic constants by use of both vibrational second-order perturbation theory and variational methods to solve the nuclear Schrödinger equation. Agreement between our best computed fundamental vibrational frequencies and recent infrared photodissociation experiments is reasonable for most bands, but there are a few exceptions. Possible sources for the discrepancies are discussed. We determine the energy difference between the cyclic and linear forms of C3H3+, obtaining 27.9 kcal/mol at 0 K, which should be the most reliable available. It is expected that the fundamental vibrational frequencies and spectroscopic constants presented here for c-C3H3+ and 1-C3H3+ are the most reliable available for the free gas-phase species, and it is hoped that these will be useful in the assignment of future high- resolution laboratory experiments or astronomical observations. [ABSTRACT FROM AUTHOR]

Published
2011
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41. The Dalton quantum chemistry program system

Author

Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, Ågren, Hans, Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, and Ågren, Hans

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42. The Dalton quantum chemistry program system

Author

Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, Ågren, Hans, Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, and Ågren, Hans

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43. The Dalton quantum chemistry program system

Author

Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, Ågren, Hans, Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, and Ågren, Hans

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44. The Dalton quantum chemistry program system

Author

Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, Ågren, Hans, Aidas, Kestutis, Angeli, Celestino, Bak, Keld L., Bakken, Vebjørn, Bast, Radovan, Boman, Linus, Christiansen, Ove, Cimiraglia, Renzo, Coriani, Sonia, Dahle, Pål, Dalskov, Erik K., Ekström, Ulf, Enevoldsen, Thomas, Eriksen, Janus J., Ettenhuber, Patrick, Fernández, Berta, Ferrighi, Lara, Fliegl, Heike, Frediani, Luca, Hald, Kasper, Halkier, Asger, Hättig, Christof, Heiberg, Hanne, Helgaker, Trygve, Hennum, Alf Christian, Hettema, Hinne, Hjertenaes, Eirik, Høst, Stinne, Høyvik, Ida-Marie, Iozzi, Maria Francesca, Jansík, Branislav, Jensen, Hans Jørgen Aa., Jonsson, Dan, Jørgensen, Poul, Kauczor, Joanna, Kirpekar, Sheela, Kjaergaard, Thomas, Klopper, Wim, Knecht, Stefan, Kobayashi, Rika, Koch, Henrik, Kongsted, Jacob, Krapp, Andreas, Kristensen, Kasper, Ligabue, Andrea, Lutnaes, Ola B., Melo, Juan I., Mikkelsen, Kurt V., Myhre, Rolf H., Neiss, Christian, Nielsen, Christian B., Norman, Patrick, Olsen, Jeppe, Olsen, Jógvan Magnus H., Osted, Anders, Packer, Martin J., Pawlowski, Filip, Pedersen, Thomas B., Provasi, Patricio F., Reine, Simen, Rinkevicius, Zilvinas, Ruden, Torgeir A., Ruud, Kenneth, Rybkin, Vladimir V., Sałek, Pawel, Samson, Claire C. M., de Merás, Alfredo Sánchez, Saue, Trond, Sauer, Stephan P. A., Schimmelpfennig, Bernd, Sneskov, Kristian, Steindal, Arnfinn H., Sylvester-Hvid, Kristian O., Taylor, Peter R., Teale, Andrew M., Tellgren, Erik I., Tew, David P., Thorvaldsen, Andreas J., Thøgersen, Lea, Vahtras, Olav, Watson, Mark A., Wilson, David J. D., Ziolkowski, Marcin, and Ågren, Hans

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48. The Hartree–Fock magnetizability of C60

Author

Hans Ågren, Trygve Helgaker, Henrik Koch, Pål Dahle, Kenneth Ruud, Peter R. Taylor, Ruud, Kenneth, Ågren, Han, Helgaker, Trygve, Dahle, Pål, Koch, Henrik, and Taylor, Peter R

Subjects
Chemistry, Hartree–Fock method, Ab initio, General Physics and Astronomy, Aromaticity, chemistry.chemical_compound, Atomic orbital, Computational chemistry, Physics::Atomic and Molecular Clusters, Diamagnetism, Molecule, Physics::Atomic Physics, Limit (mathematics), Physics::Chemical Physics, Physical and Theoretical Chemistry, Atomic physics, Benzene
Abstract

Using London atomic orbitals and a recent parallel implementation of our second-order ab initio property code, we have determined the Hartree–Fock limit for the magnetizability of C60 to be −359±5 ppm cgs, in excellent agreement with earlier basis-set limit extrapolations. Using diamagnetic exaltation as a criterion for aromaticity, our calculations show that C60 is an aromatic molecule with a relative diamagnetic exaltation greater than that of benzene.

Published
1998

49. Usefulness of new imaging methods for assessment of type B aortic dissection.

Author

Clough RE, Zymvragoudakis VE, Biasi L, and Taylor PR

Abstract

While the medical management of uncomplicated type B aortic dissection has good outcomes in the short term, the longer term mortality can be in the region of 50% at 5 years. Up to 40% of the survivors can have significant dilatation of the false lumen with the risk of aneurysm formation and death due to rupture. The results of the randomized controlled trials ADSORB and INSTEAD-XL have shown that beneficial aortic remodelling occurs after endoluminal stent graft placement, but these trials were underpowered to show any effect on survival. Static computed tomography (CT) angiography imaging methods have been used to try to identify high risk patients using parameters such as diameter, the position and size of the entry tear, and the amount of false lumen thrombus, but these so far are not able to clinically risk stratify individual patients. In this manuscript, we present our initial experience with new MR imaging methods. These have allowed us to develop a greater understanding of aortic dissection by providing information regarding the underlying hemodynamic and biomechanics of the dissection, as well as more accurate assessment of important clinical imaging endpoints, such as false lumen thrombosis.

Published
2014
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50. Hybrid aortic arch repair.

Author

Clough RE, Lotfi S, Powell J, Lee A, and Taylor PR

Abstract

Innovations in thoracic endovascular aortic repair techniques have enabled its incorporation in open procedures, resulting in a hybrid approach to aortic arch repair. The present study reported our experience with the hybrid technique in managing arch pathologies. Fifty-one patients underwent a hybrid repair of arch pathologies. 10 patients had urgent or emergency surgery, and 8 had previous abdominal aortic aneurysm repair; all were classified as high risk (ASA grade III or IV). Overall 30-day mortality was 9.8% (5/51). Hospital mortality was 30% (3/10) in urgent/emergent surgery and 4.90% (2/41) in elective cases. Ischemic stroke occurred in 11.8% (6/51) of patients, while 5.9% (3/51) experienced paraplegia. Endoleaks occurred in 8 patients, 6 of which were Type 1. Long-term patency rate was 96%. The hybrid technique is a safe, effective and less invasive alternative to open repair of arch pathologies, with comparable outcomes in high-risk patient groups. Patency rates and durability demonstrate the long-term potential of this technique.

Published
2013
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