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Accurate Potential Energy Surfaces and Beyond: Chemical Reactivity, Binding, Long-Range Interactions, and Spectroscopy Advances in Physical Chemistry Accurate Potential Energy Surfaces and Beyond: Chemical Reactivity, Binding, Long-Range Interactions, and Spectroscopy Guest Editors: Laimutis Bytautas, Joel M. Bowman, Xinchuan Huang, and António J. C. Varandas Accurate Potential Energy Surfaces and Beyond: Chemical Reactivity, Binding, Long-Range Interactions, and Spectroscopy Advances in Physical Chemistry Accurate Potential Energy Surfaces and Beyond: Chemical Reactivity, Binding, Long-Range Interactions, and Spectroscopy Guest Editors: Laimutis Bytautas, Joel M. Bowman, Xinchuan Huang, and Antonio´ J. C. Varandas Copyright © 2012 Hindawi Publishing Corporation. All rights reserved. This is a special issue published in “Advances in Physical Chemistry.” All articles are open access articles distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Editorial Board Janos´ G. Angy´ an,´ France F. Illas, Spain Eli Ruckenstein, USA M. Sabry Abdel-Mottaleb, Egypt KwangS.Kim,RepublicofKorea Gnther Rupprechter, Austria Taicheng An, China Bernard Kirtman, USA Kenneth Ruud, Norway J. A. Anderson, UK Lowell D. Kispert, USA Viktor A. Safonov, Russia Panos Argyrakis, Greece Marc Koper, The Netherlands Dennis Salahub, Canada Ricardo Aroca, Canada Alexei A. Kornyshev, UK Anunay Samanta, USA Stephen H. Ashworth, UK Yuan Kou, China Dipankar Das Sarma, India Biman Bagchi, India David Logan, UK Joop Schoonman, The Netherlands Hans Bettermann, Germany Clare M. McCabe, USA Stefan Seeger, Switzerland Vasudevanpillai Biju, Japan James K. McCusker, USA Tamar Seideman, USA Joel Bowman, USA MichaelL.McKee,USA Hiroshi Sekiya, Japan Wybren J. Buma, The Netherlands Robert M. Metzger, USA Luis Serrano-Andres,´ Spain Sylvio Canuto, Brazil Michael V. Mirkin, USA Michael D. Sevilla, USA Li Ming Dai, USA David Muddiman, USA C. David Sherrill, USA Michael Deleuze, Belgium Klaus Mullen, Germany Kenneth Showalter, USA Michael Dolg, Germany Daniel Neuhauser, USA Karl Sohlberg, USA D. James Donaldson, Canada Konstantin Neyman, Spain Miquel Sola,` Spain Ali Eftekhari, USA Minh Tho Nguyen, Belgium Vasco Teixeira, Portugal Gregory S. Ezra, USA Hiroshi Onishi, Japan Sergei Tretiak, USA Claudio Fontanesi, Italy Thomas Oppenlaender, Germany Thanh N. Truong, USA Michael J. Frisch, USA Samir K. Pal, India Frantisek Turecek, USA Paul Geerlings, Belgium Leonardo Palmisano, Italy P. Unwin, UK Robert Gerber, Israel Francesco Paolucci, Italy Eric Vauthey, Switzerland Jinlong Gong, China Jan Skov Pedersen, Denmark David Wales, UK David Wayne Goodman, USA Piotr Piecuch, USA Peter Wolynes, USA Vicki H. Grassian, USA M. P. Pileni, France Qiang Xu, Japan Lawrence Harding, USA Simon M. Pimblott, UK Yigzaw G Yohanis, UK David Brynn Hibbert, Germany Oleg Prezhdo, USA Jeffrey M. Zaleski, USA Kimihiko Hirao, Japan Colin Raston, Australia Ruhong Zhou, USA Paul L. Houston, USA Benjaram M. Reddy, India Jyh-Ping Hsu, Taiwan Ranko Richert, USA Contents Accurate Potential Energy Surfaces and Beyond: Chemical Reactivity, Binding, Long-Range Interactions, and Spectroscopy, Laimutis Bytautas, Joel M. Bowman, Xinchuan Huang, and Antonio´ J. C. Varandas Volume 2012, Article ID 679869, 4 pages ··· ··· ff The N HF Interactions in the X-Pyridazine (HF)2 Complexes: Substituent E ects and Energy Components, Ali Ebrahimi, Mostafa Habibi-Khorassani, Farideh Badichi Akher, and Abdolkarim Farrokhzadeh Volume 2012, Article ID 362608, 9 pages Potential Energy Surfaces for Reactions of X Metal Atoms (X = Cu, Zn, Cd, Ga, Al, Au, or Hg) with YH4 Molecules (Y = C, Si, or Ge) and Transition Probabilities at Avoided Crossings in Some Cases, Octavio Novaro, Mar´ıa del Alba Pacheco-Blas, and Juan Horacio Pacheco-Sanchez´ Volume 2012, Article ID 720197, 17 pages 1 1 New ab Initio Potential Energy Surfaces for the Renner-Teller Coupled 1 A and 1 A States of CH2, Haitao Ma, Chunfang Zhang, Zhijun Zhang, Xiaojun Liu, and Wensheng Bian Volume 2012, Article ID 236750, 12 pages Applications of Potential Energy Surfaces in the Study of Enzymatic Reactions, Eric A. C. Bushnell, WenJuan Huang, and James W. Gauld Volume 2012, Article ID 867409, 15 pages Quantum Instanton Evaluations of the Thermal Rate Constants for Complex Systems,YiZhaoand Wenji Wang Volume 2012, Article ID 483504, 16 pages Improved Potential Energy Surface of Ozone Constructed Using the Fitting by Permutationally Invariant Polynomial Function, Mehdi Ayouz and Dmitri Babikov Volume 2012, Article ID 951371, 9 pages Potential Energy Surface of NO on Pt(997): Adsorbed States and Surface Diffusion, N. Tsukahara and J. Yoshinobu Volume 2012, Article ID 571657, 9 pages Exploring Multiple Potential Energy Surfaces: Photochemistry of Small Carbonyl Compounds, Satoshi Maeda, Koichi Ohno, and Keiji Morokuma Volume 2012, Article ID 268124, 13 pages Ab Initio Potential Energy Surfaces for Both the Ground (X1A) and Excited (A1A) Electronic States of HSiBr and the Absorption and Emission Spectra of HSiBr/DSiBr, Anyang Li, Sen Lin, and Daiqian Xie Volume 2012, Article ID 572148, 20 pages Constructing Potential Energy Surfaces for Polyatomic Systems: Recent Progress and New Problems,J. Espinosa-Garcia, M. Monge-Palacios, and J. C. Corchado Volume 2012, Article ID 164752, 19 pages Hindawi Publishing Corporation Advances in Physical Chemistry Volume 2012, Article ID 679869, 4 pages doi:10.1155/2012/679869 Editorial Accurate Potential Energy Surfaces and Beyond: Chemical Reactivity, Binding, Long-Range Interactions, and Spectroscopy Laimutis Bytautas,1 Joel M. Bowman,2 Xinchuan Huang,3 and Antonio´ J. C. Varandas4 1 Department of Chemistry, Rice University, Houston, TX 77005, USA 2 Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, GA 30322, USA 3 SETI Institute and NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035, USA 4 Departamento de Quimica, Universidade de Coimbra, 3004535 Coimbra, Portugal Correspondence should be addressed to Laimutis Bytautas, [email protected] Received 13 February 2012; Accepted 13 February 2012 Copyright © 2012 Laimutis Bytautas et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1. Background Due to the recent advances in ab initio method devel- opment [10] primarily focusing on the solution of the Beginning with the seminal paper of Born and Oppenheimer nonrelativistic Schrodinger¨ equation, the theoretical data (BO) [1] in 1927, the concept of the potential energy surface representing PESs is of higher quality and the cost and timing (PES) plays a critical role in the description, simulation, for such calculations is considerably improved. Furthermore, and modeling of molecular systems. It provides the basis [2] the relativistic corrections [11] can be significant and should for understanding the processes associated with the nuclear be included if high accuracy of PESs is needed. For instance, motions in molecules. By going beyond the characteristic the inclusion of the spin-orbit coupling effect (relativistic stationary points and barriers, full dimensional, accurate phenomenon) may turn a crossing of two potential energy potential energy surfaces have a very broad range of applica- curves into an avoided crossing [12]. Finally, given the raw tions in many areas of physical chemistry; for example, they ab initio data, efficient fitting techniques [13]arecapable provide insight into structure, reactivity, and spectroscopy of of generating excellent analytical representations of potential molecules. While the majority of stable structures on PES are associated with the covalent or ionic bonding [3], the regions energy surfaces. One example is the functional represen- of PES dominated by van der Waals interactions are essential tation of a PES using the double many-body expansion for low-temperature phenomena and molecular stacking method [14]. Another important class of PESs corresponds which are critical for understanding biomolecular structures to the ones that are constructed to be explicitly invariant involving DNA and RNA molecules [4]. Furthermore, the with respect to all permutations of equivalent atoms [15, advances in “cold chemistry” [5] make it possible to test the 16]. It is well recognized that one of the most stringent theoretical predictions (see, e.g., [6]) involving very small criteria of the quality of the PES is its ability to reproduce < the experimental rotational-vibrational spectrum with the barriers of 15 K. At such low temperatures the quantum −1 effects, for example, tunneling, play a significant role in “near-spectroscopic” accuracy [12]ofabout10cm or chemical reactivity. For instance, the large de Broglie wave- better [17]. Occasionally, the empirical refinements for ab length of ultracold molecules entirely changes the nature of initio PESsareusedinordertoachieveaverycloseagreement < −1 reaction dynamics [7], and energy barriers on the PES play ( 0.1 cm ) with experiment for rovibrational transitions adifferent role because, in this regime, quantum tunneling [18]. becomes the dominant reaction pathway [8]. In addition, In many cases the BO approximation is valid to a high our understanding of potential energy surfaces has benefitted degree, and a single PES is sufficient to describe the motion greatly from the ability of experimentalists to study chemical of nuclei. However,
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