Poster Session

Posters presented by: P01: Adam S. Abbott, University of Georgia P02: Yasmeen Abdo, University of Mississippi P03: Vibin Abraham, Virginia Tech P04: Asim Alenaizan, Georgia Institute of Technology P05: Isuru R. Ariyanthna, Auburn University P06: Brandon W. Bakr, Georgia Institute of Technology P07: [Matthew Bassett, Georgia Southern University] P08: Alexandre P. Bazanté, University of Florida P09: Andrea N. Becker, University of Tennessee P10: Randi Beil, University of Tennessee P11: Andrea N. Bootsma, University of Georgia/Texas A&M University P12: Adam Bruner, Louisiana State University P13: Lori A. Burns, Georgia Institute of Technology P14: Chanxi Cai, Emory University P15: Katherine A. Charbonnet, University of Memphis P16: Marjory C. Clement, Virginia Tech P17: Wallace D. Derricotte, Emory University P18: Harkiran Dhah, University of Tennessee P19: Manuel Díaz-Tinoco, Auburn University P20: Vivek Dixit: Mississippi State University P21: Eric Van Dornshuld, Mississippi State University P22: Katelyn M. Dreux, University of Mississippi P23: Narendra Nath Dutta, Auburn University P24: William Earwood, University of Mississippi P25: Thomas L. Ellington, University of Mississippi P26: Marissa L. Estep, University of Georgia P27: Yanfei Guan, Texas A&M University P28: Andrew M. James, Virginia Tech P29: Yifan Jin, University of Florida P30: Dwayne John, Middle Tennessee State University P31: Sarah N. Johnson, University of Mississippi P32: Noor Md Shahriar Khan, Auburn University P33: Monika Kodrycka, Auburn University P34: Ashutosh Kumar, Virginia Tech P35: Elliot Lakner, University of Alabama P36: Robert W. Lamb, Mississippi State University P37: S. Paul Lee, University of Mississippi P38: Zachary Lee, University of Alabama P39: Conrad D. Lewis, Middle Tennessee State University P40: Guangchao Liang, Mississippi State University P41: Chenyang Li, Emory University P42: Hannah C. Lozano, University of Memphis P43: SharathChandra Mallojjala, University of Georgia/Texas A&M University P44: Zheng Ma, Duke University P45: Elvis Maradzike, Florida State University P46: Ashley S. McNeill, University of Alabama P47: Stephen R. Miller, University of Georgia P48: W. J. Morgan, University of Georgia P49: Apurba Nandi, Emory University P50: Daniel R. Nascimento, Florida State University P51: Brooke N. Nash, Mississippi College P52: Carlie M. Novak, Georgia Southern University P53: Young Choon Park, University of Florida P54: Kirk C. Pearce, Virginia Tech P55: Rudradatt (Randy) Persaud, University of Alabama P56: Karl Pierce, Virginia Tech P57: Kimberley N. Poland, University of Mississippi P58: Chen Qu, Emory University P59: Duminda S. Ranasinghe, University of Florida P60: Hailey B. Reed, University of Mississippi P61: Matthew Schieber, Georgia Institute of Technology P62: Jeffrey B. Schriber, Emory University P63: Thomas Sexton, University of Mississippi P64: Holden T. Smith, Louisiana State University P65: Aubrey Smyly, Mississippi College P66: B. T. Soto, University of Georgia P67: Trent H. Stein, University of Alabama P68: Cody J. Stephan, Georgia Southern University P69: Thomas Summers, University of Memphis P70: Zhi Sun, University of Georgia P71: Monica Vasiliu, University of Alabama P72: Jonathan M. Waldrop, Auburn University P73: Tommy Walls, Southern Louisiana University P74: Qingfeng (Kee) Wang, Emory University P75: Constance E. Warden, Georgia Institute of Technology P76: Jared D. Weidman, University of Georgia P77: Melody Williams, University of Memphis P78: Donna Xia, University of Alabama P79: Qi Yu, Emory University P80: Boyi Zhang, University of Georgia P81: Tianyuan Zhang, Emory University P82: Michael Zott, Georgia Institute of Technolog

Accurate Enthalpies of Formation of Alkali and Alkaline Earth Metal Oxides and Hydroxides: Assessment of the Correlation Consistent Composite Approach (ccCA)

Computing the enthalpies of formation for alkali metal and alkaline earth metal oxides (MxO) and hydroxides [M(OH)n] using the Gaussian-n (Gn) and Weismann-n (Wn) ab initio model chemistries is difficult due to an improper treatment of core-valence electron correlation effects. Using a new model chemistry called the correlation consistent Composite Approach (ccCA), enthalpies of formation were determined for eight different alkali/alkaline earth metal oxides and hydroxides. Unlike the Gn and Wn model chemistries, which must be modified to properly account for core-valence electron correlation, the standard implementations of the ccCA provide acceptable results, and all enthalpies of formation obtained with the ccCA are within the accepted range of recommended values

Performance of the correlation consistent composite approach for transition states: A comparison to G3B theory

This article discusses performance of the correlation consistent composite approach for transition states

Quantitative Computational Thermochemistry of Transition Metal Species

This article discusses quantitative computational thermochemistry of transition metal species. The correlation consistent Composite Approach (ccCA), which has been shown to achieve chemical accuracy (±1 kcal mol⁻¹) for a large benchmark set of main group and s-block metal compounds, is used to compute enthalpies of formation for a set of 17 3d transition metal species

Three-Coordinate Terminal Imidoiron(III) Complexes: Structure, Spectroscopy, and Mechanism of Formation

Article discussing three-coordinate terminal imidoiron(III) complexes and the structure, spectroscopy, and the mechanism of formation

The correlation consistent composite approach (cc CA

An alternative to the Gaussian-n (G1, G2, and G3) composite methods of computing molecular energies is proposed and is named the correlation consistent composite approach (ccCA, ccCA-CBS-1, ccCA-CBS-2). This approach uses the correlation consistent polarized valence (cc-pV XZ) basis sets. The G2-1 test set of 48 enthalpies of formation (ΔH f), 38 adiabatic ionization potentials (IPs), 25 adiabatic electron affinities (EAs), and 8 adiabatic proton affinities (PAs) are computed using this approach, as well as the ΔH f values of 30 more systems. Equilibrium molecular geometries and vibrational frequencies are obtained using B3LYP density functional theory. When applying the ccCA-CBS method with the cc-pVXZ series of basis sets augmented with diffuse functions, mean absolute deviations within the G2-1 test set compared to experiment are 1.33 kcal mol -1 for ΔH f, 0.81 kcal mol -1 for IPs, 1.02 kcal mol -1 for EAs, and 1.51 kcal mol -1 for PAs, without including the high-level correction (HLC) contained in the original Gn methods. Whereas the HLC originated in the Gaussian-1 method as an isogyric correction, it evolved into a fitted parameter that minimized the error of the composite methods, eliminating its physical meaning. Recomputing the G1 and G3 enthalpies of formation without the HLC reveals a systematic trend where most ΔH f values are significantly higher than experimental values. By extrapolating electronic energies to the complete basis set (CBS) limit and adding G3-like corrections for the core-valence and infinite-order electron correlation effects, ccCA-CBS-2 often underestimates the experimental ΔH f, especially for larger systems. This is desired as inclusion of relativistic and atomic spin-orbit effects subsequently improves theoretical ΔH f values to give a 0.81 kcal mol -1 mean absolute deviation with ccCA-CBS-2. The ccCA-CBS method is a viable black box method that can be used on systems with at least 10-15 heavy atoms. © 2006 American Institute of Physics

The correlation-consistent composite approach: Application to the G3/99 test set

Article discussing research on the correlation consistent composite approach (ccCA) and an application to the G3/99 test set

What a difference a decade has not made: The murky electronic structure of iron monocyanide (FeCN) and iron monoisocyanide (FeNC)

Formidable multireference character is known to exist in the quartet states of the neutral radicals iron monocyanide (FeCN) and iron monoisocyanide (FeNC), even more so than the controversial FeH radical (which is now definitively known to have a 4Δ ground electronic state). In the initial theoretical study, it was found that the gas phase adiabatic 4Δ ← 6Δ transition energy plummeted with improving treatment of dynamical correlation, and final results suggested that FeCN (4Δ) and FeNC (6Δ) isomers have different ground electronic states. The 4Δ ground state for FeCN has been since verified experimentally. In this work, an ab initio composite method employing coupled cluster theory up to full quadruple excitations (CCSDTQ) and large basis set CCSDT computations is compared to multireference configuration interaction (MRCI) energies at a level of sophistication far superior to the 2004 study [DeYonker et al. J. Chem. Phys. 2004, 120, 4726]. Despite advances in the treatment of scalar relativistic effects, improved iron basis sets, and massive increases in computer processing power over the past decade, multireference methodologies still fail to find the correct ground state for FeCN, with large basis set MRCISD+Q results providing a qualitatively poor adiabatic 4Δ ← 6Δ transition energy, in error by nearly 5000 cm-1. Coupled cluster theory with post-CCSD(T) additive corrections produces the 4Δ FeCN ground state, with the 6Δ state only 306 cm-1 higher in energy. The ground electronic state of FeNC is computed to be 6Δ and is only 45 cm-1 higher in energy than the 4Δ FeCN state while it is 741 cm-1 lower in energy than the FeNC 4Δ excited state. Surprisingly, an additional CCSDT additive correction for core-valence correlation shifts the FeNC transition energy in favor of a 4Δ ground state, with a 4Δ ← 6Δ Te of 227 cm-1. (Chemical Presented)