11810 Inorganic Chemistry, Vol. 48, No. 24, 2009
Zhang et al.
Reports on transition metal selenites or tellurites with addi-
tional d0 transition metal ions are still rare.8b,15,16 Several phases
in ZnII/CdII-VV-SeIV/TeIV-O system have been reported in
our laboratory, among which Cd4V2Te3O15 displays a moder-
ately SHG response of 1.4 times that of KH2PO4 (KDP).15b,c
Furthermore, Ni3(Mo2O8)(SeO3) and Ni3(Mo2O8)(TeO3) with
interesting ferromagnetic properties have also been reported.15a
We believe that more systematic investigations on the TM-
d0TM-TeIV(or SeIV)-O systems may lead to more SHG and
magnetic materials and provide further insights on their
structure-property relationships. Our systematic explorations
of new SHG materials in the TM-MoVI-SeIV/TeIV-O system
afforded five new transition metal molybdenum(VI) selenites
or tellurites, namely, TM(MoO3)(SeO3)(H2O) (TM = Mn,
Co), Fe2(Mo2O7)(SeO3)2(H2O), Cu2(MoO4)(SeO3), and Ni3-
(MoO4)(TeO3)2. Mn(MoO3)(SeO3)(H2O) displays a moder-
ately strong SHG efficiency of about 3 times that of KDP
whereas the SHG signal of Ni3(MoO4)(TeO3)2 is much weaker
than that of KDP. Herein we report their syntheses, crystal
structure, optical properties, as well as magnetic properties.
Preparation of Mn(MoO3)(SeO3)(H2O). A mixture of 0.4
mmol MoO3, 0.4 mmol MnCO3, 1.2 mmol SeO2, and H2O (5 mL)
wassealedinanautoclaveequippedwithaTeflonlinear(23mL) and
heated at 210 ꢀC for 4 days, followed by slow cooling to room
temperature at a rate of 6 ꢀC/h. Yellow brick-shaped crystals of
Mn(MoO3)(SeO3)(H2O) were recovered. The energy-dispersive
spectrometry (EDS) elemental analyses gave the molar ratio of
Mn/Mo/Se of 1.0:1.3:1.3, which is in good agreement with the one
determined from single crystal X-ray structural analysis. After proper
structural analysis, Mn(MoO3)(SeO3)(H2O) was obtained as
a single-phase by the reaction of a mixture of 0.4 mmol MoO3,
0.4 mmol MnCO3, and 0.4 mmol SeO2 in 5 mL H2O at 210 ꢀC for
4 days. The yield is about 40% (based on Mo), and its purity was
confirmed by XRD studies (Supporting Information). IR data (KBr,
cm-1): 3147(s), 1635 (s), 941 (w), 914 (s), 896 (s), 852 (m), 821 (m),
727 (m), 688(s), 584(s), 509(s).
Preparation of Co(MoO3)(SeO3)(H2O). A mixture of 0.4
mmol MoO3, 0.4 mmol CoCl2, 1.2 mmol SeO2, and H2O (5 mL)
was sealed in an autoclave equipped with a Teflon linear (23 mL)
and heated at 210 ꢀC for 4 days, followed by slow cooling to room
temperature at a rate of 6 ꢀC/h. Brown plate-shaped crystals of
Co(MoO3)(SeO3)(H2O) were recovered. The energy-dispersive
spectrometry (EDS) elemental analyses gave the molar ratio of
Co/Mo/Se of 1.0:1.3:1.4, which is in good agreement with the one
determined from single crystal X-ray structural analysis. After
proper structural analysis, Co(MoO3)(SeO3)(H2O) was obtained
as a single-phase by the reaction of a mixture of 0.4 mmol MoO3,
0.4 mmol CoCl2, and 1.2 mmol SeO2 in 5 mL of H2O at 210 ꢀC for
4 days. The yield is about 16% (based on Mo), and its purity was
confirmed by XRD studies (Supporting Information). IR data
(KBr, cm-1): 3251(s), 3141 (s), 1571(m), 923 (s), 873 (s), 844 (s),
798 (w), 692 (m), 619 (s), 507 (s), 472(w).
Experimental Section
Materials and Methods. All of the chemicals were analytically
pure, obtained from commercial sources, and used without further
purification. Transition-metal oxides, manganous carbonate,
cobalt(II) chloride were purchased from the Shanghai Reagent
Factory, and SeO2 (99þ %) and TeO2 (99þ %) were purchased
from ACROS ORGANICS. NiO was synthesized by heating
Ni2O3 in air at 610 ꢀC for 12 h, and its purity was checked by
X-ray powder diffraction (XRD). Microprobe elemental analyses
were performed on a field emission scanning electron microscope
(FESEM, JSM6700F) equipped with an energy dispersive X-ray
spectroscope (EDS, Oxford INCA). The XRD data were collected
on a Panalytical X’pert Pro MPD diffractometer using graphite-
monochromated Cu KR radiation in the 2θ range of 5-65ꢀ with a
step size of 0.02ꢀ. The absorption spectra were determined by the
diffuse-reflection technique.17a F(R) and R are linked by F(R) =
(1 - R)2/2R,17b where R is reflectance and F(R) is the Kubelka-
Munk remission function. The minima in the second derivative
curves of the Kubelka-Munk function are taken as the position of
the absorption bands. TGA studies were all carried out with
NETZSCH STA 449C instruments. The sample and reference
(Al2O3) were enclosed in a platinum crucible and heated at a rate
of 10 ꢀC/min from room temperature to 1000 ꢀC under a nitrogen
atmosphere. The IR spectra were recorded on a Magna 750 FT-IR
spectrometer as KBr pellets in the range of 4000-400 cm-1. BaSO4
plate was used as a standard (100% reflectance). The measurements
of the powder frequency-doubling effects were carried out by means
of the method of Kurtz and Perry.18 The fundamental wavelength is
1064 nm generated by a Q-switched Nd:YAG laser. The SHG
wavelength is 532 nm. KDP was used as reference to assume the
effect. Magnetic susceptibility measurements on polycrystalline
samples were performed with a PPMS-9T magnetometer at a field
of at 1000 or 5000 Oe in the temperature range 2-300 K. The raw
data were corrected for the susceptibility of the container and the dia-
magnetic contributions of the samples using pascal’s constants.19
Preparation of Fe2(Mo2O7)(SeO3)2(H2O). A mixture of 0.4
mmol MoO3, 0.4 mmol Fe2O3, 1.2 mmol SeO2, and H2O (5 mL)
was sealed in an autoclave equipped with a Teflon linear (23 mL)
and heated at 230 ꢀC for 4 days, followed by slow cooling to room
temperature at a rate of 6 ꢀC/h. Red brick-shaped crystals of
Fe2(Mo2O7)(SeO3)2(H2O) were recovered. The energy-dispersive
spectrometry (EDS) elemental analyses gave the molar ratio of Fe/
Mo/Se of 1.0:1.3:1.1, which is in good agreement with the one
determined from single crystal X-ray structural analysis. After
proper structural analysis, Fe2(Mo2O7)(SeO3)2(H2O) was obta-
ined as a single-phase by the reaction of a mixture of 0.4 mmol
MoO3, 0.4 mmol Fe2O3, and 1.2 mmol SeO2 in 5 mL of H2O at
230 ꢀC for 4 days. The yield is about 35% (based on Mo), and its
purity was confirmed by XRD studies (Supporting Information).
IR data (KBr, cm-1): 3305(w), 1643(w), 1456(w), 962(s), 910 (s),
854 (s),744 (s), 663 (m), 601 (m), 507 (m), 460 (s).
Preparation of Cu2(MoO4)(SeO3). A mixture of 0.4 mmol
MoO3, 0.4 mmol CuO, 0.4 mmol SeO2 and H2O (5 mL) was
sealed in an autoclave equipped with a Teflon linear (23 mL) and
heated at 210 ꢀC for 4 days, followed by slow cooling to room
temperature at a rate of 6 ꢀC/h. Green brick-shaped crystals of
Cu2(MoO4)(SeO3) were recovered. The energy-dispersive spectro-
metry (EDS) elemental analyses gave the molar ratio of Cu/Mo/Se
of 2.5:1.3:1.0, which is in good agreement with the one determined
from single crystal X-ray structural analysis. After proper struc-
tural analysis, Cu2(MoO4)(SeO3) was obtained as a single-phase
by the reaction of a mixture of 0.4 mmol MoO3, 0.4 mmol CuO,
0.4 mmol SeO2 in 5 mL H2Oat 210 ꢀC for 4 days. The yield is about
31% (based on Mo), and its purity was confirmed by XRD studies
(Supporting Information). IR data (KBr, cm-1): 919(w), 869 (s),
806 (w), 711 (s),561 (m), 512 (m), 470 (m).
(15) (a) Jiang, H. L.; Xie, Z.; Mao, J. G. Inorg. Chem. 2007, 46, 6495.
(b) Jiang, H. L.; Huang, S. P.; Fan, Y.; Mao, J. G.; Cheng, W. D. Chem.;Eur. J. 2008,
14, 1972. (c) Jiang, H. L.; Kong, F.; Fan, Y.; Mao, J. G. Inorg. Chem. 2008, 47, 7437.
(16) (a) Kim, Y. T.; Kim, Y. H.; Park, K.; Kwon, Y. U.; Young, V. G., Jr.
J. Solid State Chem. 2001, 161, 23. (b) Halasyamani, P. S.; O'Hare, D. Inorg.
Chem. 1997, 36, 6409.
(17) (a) Kubelka, P.; Munk, F. Z. Tech. Phys. 1931, 12, 593. (b) Wendlandt,
W. W.; Hecht, H. G. Reflectance Spectroscopy; Interscience: New York, 1966.
(18) Kurtz, S. W.; Perry, T. T. J. Appl. Phys. 1968, 39, 3798.
(19) Theory and Applications of Molecular Paramagnetism; Boudreaux,
E. A., Mulay, L. N., Eds.; John Wiley & Sons: New York, 1976.
Preparation of Ni3(MoO4)(TeO3)2. Red prism-shaped crystals
of Ni3(MoO4)(TeO3)2 were initially prepared by the high tempera-
ture solid-state reaction of a mixture of 0.64 mmol of NiO,
0.32 mmol of MoO3, and 1.6 mmol of TeO2. The reaction mixture
was thoroughly ground and pressed into a pellet, which was then
sealed into an evacuated quartz tube. The sample was allowed to