Computational Tools for Predictive Modeling of Properties in Complex Actinide Systems
Abstract
In this chapter we focus on methodological and computational aspects that are key to accurately modeling the spectroscopic and thermodynamic properties of molecular systems containing actinides within the density functional theory (DFT) framework. Our focus is on properties that require either an accurate relativistic allelectron description or an accurate description of the dynamical behavior of actinide species in an environment at finite temperature, or both. The implementation of the methods and the calculations discussed in this chapter were done with the NWChem software suite (Valiev et al. 2010). In the first two sections we discuss two methods that account for relativistic effects, the ZORA and the X2C Hamiltonian. Section 1.2.1 discusses the implementation of the approximate relativistic ZORA Hamiltonian and its extension to magnetic properties. Section 1.3 focuses on the exact X2C Hamiltonian and the application of this methodology to obtain accurate molecular properties. In Section 1.4 we examine the role of a dynamical environment at finite temperature as well as the presence of other ions on the thermodynamics of hydrolysis and exchange reaction mechanisms. Finally, Section 1.5 discusses the modeling of XAS (EXAFS, XANES) properties in realistic environments accounting for both the dynamics of the system and (for XANES)more »
 Authors:
 Publication Date:
 Research Org.:
 Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1179509
 Report Number(s):
 PNNLSA101465
44669; KC0302030
 DOE Contract Number:
 AC0576RL01830
 Resource Type:
 Book
 Resource Relation:
 Related Information: Computational Methods in Lanthanide and Actinide Chemistry, 299342
 Country of Publication:
 United States
 Language:
 English
 Subject:
 Lanthanide; actinide; chemistry; density functional theory; NWChem; calculations; Environmental Molecular Sciences Laboratory
Citation Formats
Autschbach, Jochen, Govind, Niranjan, Atta Fynn, Raymond, Bylaska, Eric J., Weare, John H., and de Jong, Wibe A. Computational Tools for Predictive Modeling of Properties in Complex Actinide Systems. United States: N. p., 2015.
Web. doi:10.1002/9781118688304.ch12.
Autschbach, Jochen, Govind, Niranjan, Atta Fynn, Raymond, Bylaska, Eric J., Weare, John H., & de Jong, Wibe A. Computational Tools for Predictive Modeling of Properties in Complex Actinide Systems. United States. doi:10.1002/9781118688304.ch12.
Autschbach, Jochen, Govind, Niranjan, Atta Fynn, Raymond, Bylaska, Eric J., Weare, John H., and de Jong, Wibe A. 2015.
"Computational Tools for Predictive Modeling of Properties in Complex Actinide Systems". United States.
doi:10.1002/9781118688304.ch12.
@article{osti_1179509,
title = {Computational Tools for Predictive Modeling of Properties in Complex Actinide Systems},
author = {Autschbach, Jochen and Govind, Niranjan and Atta Fynn, Raymond and Bylaska, Eric J. and Weare, John H. and de Jong, Wibe A.},
abstractNote = {In this chapter we focus on methodological and computational aspects that are key to accurately modeling the spectroscopic and thermodynamic properties of molecular systems containing actinides within the density functional theory (DFT) framework. Our focus is on properties that require either an accurate relativistic allelectron description or an accurate description of the dynamical behavior of actinide species in an environment at finite temperature, or both. The implementation of the methods and the calculations discussed in this chapter were done with the NWChem software suite (Valiev et al. 2010). In the first two sections we discuss two methods that account for relativistic effects, the ZORA and the X2C Hamiltonian. Section 1.2.1 discusses the implementation of the approximate relativistic ZORA Hamiltonian and its extension to magnetic properties. Section 1.3 focuses on the exact X2C Hamiltonian and the application of this methodology to obtain accurate molecular properties. In Section 1.4 we examine the role of a dynamical environment at finite temperature as well as the presence of other ions on the thermodynamics of hydrolysis and exchange reaction mechanisms. Finally, Section 1.5 discusses the modeling of XAS (EXAFS, XANES) properties in realistic environments accounting for both the dynamics of the system and (for XANES) the relativistic effects.},
doi = {10.1002/9781118688304.ch12},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2015,
month = 3
}

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