NpO2点缺陷的结构和能量性质的DFT+U研究

doi:10.19596/j.cnki.1001-246x.8838

摘要/Abstract

摘要：

通过DFT+U方法计算NpO₂的不同磁性结构和能量随U值(3~7 eV)的变化关系, 选取U为4.0 eV时研究NpO₂中不同点缺陷对其体系结构和能量性质的影响。在NpO₂的三种不同磁性结构的优化计算结果中, 3 k AFM的结构优化结果和实验值吻合较好且具有较低形成能。与完美结构比较, 单O空位体系形成能增加约0.06 eV, 而Np空位则使得体系形成能增加1.4 eV。还研究了随着O空位数和Np空位数的增加, 体系的体积和能量的变化。

关键词: NpO₂, 点缺陷, 形成能, 密度泛函理论

Abstract:

The relationship between different magnetic structures and energies of NpO₂ with a series of U values (3~7 eV) is first calculated by DFT+U method, and then the influence of different point defects in NpO₂ on its architecture and energy properties is studied according to reliable U (4.0 eV). In the calculated results of three different magnetic orders of NpO₂, the structural results of 3 k AFM are in good agreement with the experimental values and obtained a lower energy of formation. Compared with the perfect structure of NpO₂, the energy of formation of single O vacancy system increase by about 0.06 eV, while the energy of formation of the single Np vacancy system increase by 1.4 eV. In addition, we also study the changes in the volume and energy of the system as O and Np vacancies increase.

Key words: NpO₂, point defects, energy of formation, density functional theory

刘涛, 高涛. NpO₂点缺陷的结构和能量性质的DFT+U研究[J]. 计算物理, 2025, 42(1): 84-89.

Tao LIU, Tao GAO. Structural and Energetic Properties for Point Defects in NpO₂ from DFT+U Calculations[J]. Chinese Journal of Computational Physics, 2025, 42(1): 84-89.

图/表 7

图1 NpO2的晶体结构(a)铁磁(1 k FM); (b)反铁磁(1 k AFM)；(c)反铁磁(3 k AFM)

Fig.1 Crystal structure of NpO2 (a) 1 k ferromagnetic (FM) order; (b) longitudinal 1 k collinear antiferromagnetic (AFM) order; (c) transverse 3 k noncollinear antiferromagnetic (AFM) order

图2 PBEsol+U计算的NpO2的(a)晶格常数和(b)能量随U值的变化

Fig.2 Variations (a) lattice parameters and (b) energy of NpO2 calculated by PBEsol+U with U

表1 PBEsol+U方法计算的金属Np、O2和NpO2结构的晶格参数a和能量Etot

Table 1 Lattice constants a and Etot of metal Np, O2 and NpO2 calculated by PBEsol+U method

		Np	O₂	NpO₂
a/nm	PBEsol+U	0.394		0.543
a/nm	Exp.[3]	0.393		0.544
E_tot/eV	PBEsol+U	-17.405	-5.014	-24.938
E_tot/eV	Exp.[5]		-4.9

图3 不同点缺陷结构(a) 单O空位; (b) 单Np空位

Fig.3 Different point defect structures (a) single O vacancy; (b) single Np vacancy

表2 PBEsol+U方法计算的不同NpO2缺陷结构的晶格参数a、能量Etot、形成能Eform

Table 2 Lattice constants a、Etot、Eform calculated by PBEsol+U method

	Method	a/nm	E_tot/eV	E_form/eV
Np₃₂O₆₄	PBEsol+U	1.089	-24.938	-11.225
Np₃₂O₆₄	Exp. [3]	1.088	-24.938	-11.225
Np₃₂O₆₃	PBEsol+U	1.089	-25.217	-11.166
Np₃₂O₆₂	PBEsol+U	1.089	-24.941	-11.158
Np₃₂O₆₁	PBEsol+U	1.091	-24.689	-11.197
Np₃₁O₆₄	PBEsol+U	1.086	-24.771	-9.886
Np₃₀O₆₃	PBEsol+U	1.085	-24.164	-8.829

图4 不同点缺陷结构的能量变化

Fig.4 Energy variation and various point defect structures

图5 不同O点缺陷和Np点缺陷的结构参数与能量的变化关系

Fig.5 Relationship between structural parameters and energy of various O point defects and Np point defects

参考文献 17

1	SERIZAWA H, ARAI Y, NAKAJIMA K. The estimation of the heat capacity of NpO₂[J]. The Journal of Chemical Thermodynamics, 2001, 33(6): 615- 628. DOI
2	YAMASHITA T, NITANI N, TSUJI T, et al. Thermal expansions of NpO₂ and some other actinide dioxides[J]. Journal of Nuclear Materials, 1997, 245(1): 72- 78. DOI
3	BENEDICT U, DABOS S, DUFOUR C, et al. Neptunium compounds under high pressure[J]. Journal of the Less Common Metals, 1986, 121, 461- 468. DOI
4	SANTINI P, CARRETTA S, AMORETTI G, et al. Multipolar interactions in f-electron systems: The paradigm of actinide dioxides[J]. Reviews of Modern Physics, 2009, 81, 807- 863. DOI
5	SEIBERT A, GOUDER T, HUBER F. Reaction of neptunium with molecular and atomic oxygen: Formation and stability of surface oxides[J]. Journal of Nuclear Materials, 2009, 389(3): 470- 478. DOI
6	VEAL B W, LAM D J, DIAMOND H, et al. X-ray photoelectron-spectroscopy study of oxides of the transuranium elements Np, Pu, Am, Cm, Bk, and Cf[J]. Physical Review B, 1977, 15, 2929- 2942. DOI
7	DUDAREV S L, BOTTON G A, SAVRASOV S Y, et al. Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+U study[J]. Physical Review B, 1998, 57, 1505- 1509. DOI
8	WANG Baotian, SHI Hongliang, LI Weidong, et al. First-principles LDA+U and GGA+U study of neptunium dioxide[J]. Physical Review B, 2010, 81, 045119. DOI
9	PELIN C, ELOIRDI R, HUBER F, et al. Surface reduction of neptunium dioxide and uranium mixed oxides with plutonium and thorium by photocatalytic reaction with ice[J]. Journal of Physical Chemistry C, 2015, 119(3): 1330- 1337. DOI
10	MALDONADO P, PAOLASINI L, OPPENEER P M, et al. Crystal dynamics and thermal properties of neptunium dioxide[J]. Physical Review B, 2016, 93, 144301. DOI
11	BO Tao, LAN Jianhui, ZHAO Yaolin, et al. Surface properties of NpO₂ and water reacting with stoichiometric and reduced NpO₂ (111), (110), and (100) surfaces from ab initio atomistic thermodynamics[J]. Surface Science, 2016, 644, 153- 164. DOI
12	PERUSKI K M, POWELL B A. Effect of calcination temperature on neptuniumdioxide microstructure and dissolution[J]. Environmental Science: Nano, 2020, 7, 3869- 3876. DOI
13	HOHENBERG P, KOHN W. Inhomogeneous electron gas[J]. Physical Review B, 1964, 136, 864- 871. DOI
14	KRESSE G, FURTHMÜLLER J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set[J]. Physical Review B, 1996, 54(16): 11169- 11186. DOI
15	BLÖCHL P E. Projector augmented-wave method[J]. Physical Review B, 1994, 50(24): 17953- 17979. DOI
16	KRESSE G J, JOUBERT D. From ultrasoft pseudopotentials to the projector augmented wave method[J]. Physical Review B, 1999, 59(3): 1758- 1775. DOI
17	PEGG J T, APARICIO-ANGLÈS X, STORR M, et al. DFT+U study of the structures and properties of the actinide dioxides[J]. Journal of Nuclear Materials, 2017, 492, 269- 278. DOI

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NpO₂点缺陷的结构和能量性质的DFT+U研究

Structural and Energetic Properties for Point Defects in NpO₂ from DFT+U Calculations

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