Computational Study of Cage Like (ZnO)
12
Cluster Using Hybrid and Hybrid Meta
Functionals
Manuel Alberto Flores-Hidalgo,
a
Daniel Glossman-Mitnik,
a
D. H. Galvan
b
and
Diana Barraza-Jimenez
c,
*
a
Computational Simulation and Modeling, Advanced Materials Research Center, S.C, Miguel de Cervantes 120,
Complejo Industrial Chihuahua, Chih. 31109, México
b
Physical Chemistry Nanomaterials, Nanoscience and Nanotechnology Center, UNAM, Apdo. Postal 2681, Ensenada,
Baja California, Mexico
c
Computational Chemistry, Research Center in Food and Development, A.C., Av. cuarta sur 3820, Fracc. Vencedores del
Desierto, Delicias, Chih. 33089, Mexico
(Received: Aug. 10, 2012; Accepted: Feb. 6, 2013; Published Online: Apr. 2, 2013; DOI: 10.1002/jccs.201200439)
Density Functional Theory employing hybrid and M06 functionals in combination with three different ba-
sis sets is used to calculate the ground state of a cage like (ZnO)
12
nanocluster which has been consistently
reported as the more stable cluster for its particular size. B3LYP and B3PW91 hybrid functionals com-
bined with 6-31+G*, Lanl2dz and SDD basis sets are employed to treat the ZnO molecular system. Alter-
natively, three M06 functionals in combination with three basis sets are employed in the nanostructure cal-
culations. Results obtained by treating ZnO sodalite cage nanocluster with M06 functionals demonstrated
comparable quality to results obtained with hybrid functionals. Within this study, efficient theoretical
DFT methods with the widely known hybrid and the recently created M06 meta-hybrid functionals are
employed to study nanostructured ZnO. Our resulting parameters provide a fresh approach performance
wise on the different theoretical methods to treat transition metal nanostructures, particularly, ZnO
nanoclusters geometry and electronic structure.
Keywords: Zinc oxide; Nanoclusters; Sodalite; DFT; Theoretical; B3LYP; M06.
INTRODUCTION
ZnO nanostructures in diverse forms, such as nano-
tubes,
1
nanowires,
2
nanosprings,
3
nanobelts,
4
nanorings,
5
nanohelixes,
6
and nanocages
7
represent a great opportunity
to develop new materials for opto-electronics, photovol-
taics, sensors and other interesting applications. Studies of
small ZnO nanoclusters
8
have predicted energetically low
lying isomers, such as small nanoclusters in their most sta-
ble atomic structure which are interesting because of their
discrete electronic structure that confers them special fea-
tures (e.g. optical, magnetic, chemical). Properties at the
nanostructure level are unique and may change dramati-
cally upon modifying the particle size. Theoretical studies
of small nanoparticles provide fundamental predictions of
the size-dependent limits of bulk-like materials properties.
Several studies currently available have reported novel
small ZnO nanoclusters,
9
medium size ZnO clusters,
10-14
as
well as ZnS nanoclusters.
15
Other teams have worked with
(ZnO)
n
cluster variants including n = 12, such as the case of
Al-Sunaidi et al.
16
In their work they report the stable and
low energy metastable structures of zinc oxide clusters
(ZnO)
n
with n = 1-32.
Most authors that worked with small or medium size
ZnO nanoclusters concur that the structure known as
sodalite cage, a T
h
symmetry shaped by eight hexagons and
six isolated squares, is the more stable among (ZnO)
12
nanoclusters. Matxain et al.,
10
Wang et al.,
17
Al-Sunaidi et
al., etc.
16
Behrman et al.
18
agreed on sodalite cage is a
(ZnO)
12
motif, highlighted sodalite cage as a possible
magic number structure. (ZnO)
12
geometry has raised in-
creasing interest and has been studied with different meth-
odologies like Time-of-flight mass spectra,
19
genetic algo-
rithm (GA) simulation,
20,21
all of them including electronic
structure methodology.
17,22
Zandler et al.
11
investigated
structure stability for a whole range of binary compounds
and made useful insight in metal nanostructures. Similar
results as in ZnO clusters were observed in other II-VI and
III-V binary compound clusters.
23-34
Density functional
theory (DFT) has proved great advances in nanomaterials
simulation. Some DFT pioneers expressed high hopes re-
garding hybrid functionals,
35
for example, Martell and
co-workers
36
through extensive testing concluded that the
1082 © 2013 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim J. Chin. Chem. Soc. 2013, 60, 1082-1091
Article
* Corresponding author. Tel: +52 (639)474-8400; Fax: +52 (639)474-8704; Email: dbarraza@ciad.mx
JOURNAL OF THE CHINESE
CHEMICAL SOCIETY