Synthesis and thermoelectric properties of BaMn2Sb2 single crystals

Wang, H.F.; Cai, Kefeng; Li, H.; Wang, L.; Zhou, C.W.

doi:10.1016/j.jallcom.2008.10.080

Cited by 32 publications

(18 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The fit gave intrinsic Ea value of 0.114 eV, which is comparable to those reported for BaMn2P2 (0.07 eV), 15 BaMn2As2 (0.03 eV) 16 and BaMn2Sb2 (0.03  0.10 eV) 17,18 (note that these crystals have the same 122-type structure). Thus we conclude that the intrinsic Ea is 0.114 eV and thus the bandgap is Eg = 2Ea = 0.23 eV.…”

Section: Resultssupporting

confidence: 83%

“…The similar difference in the bandgap is observed also in the Mn-based compounds (i.e. 0.14 eV for BaMn2P2, 15 1.7 eV for LaMnPO, 5 0.06 eV for BaMn2As2, 16 1.5 eV for LaMnAsO, 5 0.06  0.20 eV for BaMn2Sb2, 17,18 1.0 eV for LaMnSbO 5 ). Here, we discuss the electronic structures of β-BaZn2As2 and LaZnAsO, where we focus on the origins of the narrow bandgap in β-BaZn2As2.…”

Section: Resultssupporting

confidence: 75%

See 1 more Smart Citation

Narrow Bandgap in β-BaZn₂As₂ and Its Chemical Origins

Xiao¹,

Hiramatsu²,

Ueda

et al. 2014

J. Am. Chem. Soc.

View full text Add to dashboard Cite

β-BaZn2As2 is known to be a p-type semiconductor with the layered crystal structure similar to that of LaZnAsO, leading to the expectation that β-BaZn2As2 and LaZnAsO have similar bandgaps; however, the bandgap of β-BaZn2As2 (previously-reported value ~0.2 eV) is one order of magnitude smaller than that of LaZnAsO (1.5 eV). In this paper, the reliable bandgap value of β-BaZn2As2 is determined to be 0.23 eV from the intrinsic region of the temperature dependence of electrical conductivity. The origins of this narrow bandgap are discussed based on the chemical bonding nature probed by 6 keV hard X-ray photoemission spectroscopy, hybrid density functional calculations, and the ligand theory. One origin is the direct As-As hybridization between adjacent [ZnAs] layers, which leads to a secondary splitting of As 4p levels and raises the valence band maximum. The other is that the non-bonding Ba 5dx2y2 orbitals form unexpectedly deep conduction band minimum (CBM) in β-BaZn2As2 although the CBM of LaZnAsO is formed mainly of Zn 4s. These two origins provide a quantitative explanation for the bandgap difference between β-BaZn2As2 and LaZnAsO.

show abstract

Section: Resultssupporting

confidence: 83%

Section: Resultssupporting

confidence: 75%

Narrow Bandgap in β-BaZn₂As₂ and Its Chemical Origins

Xiao¹,

Hiramatsu²,

Ueda

et al. 2014

J. Am. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…For BaMn 2 Sb 2 , the data between (i) 240 and 400 K and between (ii) 80 and 140 K are nearly linear in T and were separately fitted by Eq. (1), yielding the intrinsic and extrinsic activation energies 1 = 0.16 eV and 2 = 0.018 eV, respectively, corroborating previous results [28]. The fits are shown as the solid straight lines in the inset of Fig.…”

Section: Methodssupporting

confidence: 90%

“…These pnictides include metallic Co-based [7][8][9][10][11][12][13][14][15], itinerant AFM Cr-based [16][17][18][19][20][21][22][23][24], semiconducting AFM Mn-based [25][26][27][28][29][30][31][32][33], and superconducting Ni-based [34][35][36][37] compounds.…”

Section: Introductionmentioning

confidence: 99%

Antiferromagnetism in semiconductingSrMn2Sb2andBaMn2Sb2single crystals

et al. 2018

View full text Add to dashboard Cite

Crystals of SrMn 2 Sb 2 and BaMn 2 Sb 2 were grown using Sn flux and characterized by powder and singlecrystal x-ray diffraction, respectively, and by single-crystal electrical resistivity ρ , heat capacity C p , and magnetic susceptibility χ measurements versus temperature T , and magnetization versus field M ( H ) isotherm measurements. SrMn 2 Sb 2 adopts the trigonal CaAl 2 Si 2 -type structure, whereas BaMn 2 Sb 2 crystallizes in the tetragonal ThCr 2 Si 2 -type structure. The ρ ( T ) data indicate semiconducting behaviors for both compounds with activation energies of ≳ 0.35 eV for SrMn 2 Sb 2 and 0.16 eV for BaMn 2 Sb 2 . The χ ( T ) and C p ( T ) data reveal antiferromagnetic (AFM) ordering at T N = 110 K for SrMn 2 Sb 2 and 450 K for BaMn 2 Sb 2 . The anisotropic χ ( T ≤ T N ) data also show that the ordered moments in SrMn 2 Sb 2 are aligned in the hexagonal a b plane, whereas the ordered moments in BaMn 2 Sb 2 are aligned collinearly along the tetragonal c axis. The a b -plane M ( H ) data for SrMn 2 Sb 2 exhibit a continuous metamagnetic transition at low fields 0 < H ≲ 1 T, whereas BaMn 2 Sb 2 exhibits no metamagnetic transitions up to 5.5 T. The χ ( T ) and C p ( T ) data for both SrMn 2 Sb 2 and BaMn 2 Sb 2 indicate strong dynamic short-range AFM correlations above their respective T N up to at least 900 K within a local-moment picture, corresponding to quasi-two-dimensional magnetic behavior. The present results and a survey of the literature for Mn pnictides with the CaAl 2 Si 2 and ThCr 2 Si 2 crystal structures show that the T N values for the CaAl 2 Si 2 -type compounds are much smaller than those for the ThCr 2 Si 2 -type materials. Crystals of SrMn 2 Sb 2 and BaMn 2 Sb 2 were grown using Sn flux and characterized by powder and singlecrystal x-ray diffraction, respectively, and by single-crystal electrical resistivity ρ, heat capacity C p , and magnetic susceptibility χ measurements versus temperature T , and magnetization versus field M(H ) isotherm measurements. SrMn 2 Sb 2 adopts the trigonal CaAl 2 Si 2 -type structure, whereas BaMn 2 Sb 2 crystallizes in the tetragonal ThCr 2 Si 2 -type structure. The ρ(T ) data indicate semiconducting behaviors for both compounds with activation energies of 0.35 eV for SrMn 2 Sb 2 and 0.16 eV for BaMn 2 Sb 2 . The χ (T ) and C p (T ) data reveal antiferromagnetic (AFM) ordering at T N = 110 K for SrMn 2 Sb 2 and 450 K for BaMn 2 Sb 2 . The anisotropic χ (T T N ) data also show that the ordered moments in SrMn 2 Sb 2 are aligned in the hexagonal ab plane, whereas the ordered moments in BaMn 2 Sb 2 are aligned collinearly along the tetragonal c axis. The ab-plane M(H ) data for SrMn 2 Sb 2 exhibit a continuous metamagnetic transition at low fields 0 < H 1 T, whereas BaMn 2 Sb 2 exhibits no metamagnetic transitions up to 5.5 T. The χ (T ) and C p (T ) data for both SrMn 2 Sb 2 and BaMn 2 Sb 2 indicate strong dynamic short-range AFM correlations above their respective T N up to at least 900 K within a local-moment picture, corresponding to quasi-two...

show abstract

“…The 2D-curvature is an improved version of the laplacian to track dispersive features in image plots, which is based on the Gauss theory of curvature. We observe two hole bands at the BZ center, none of them crossing E F , as expected from the antiferromagnetic ground state and semiconducting behavior of BaMn 2 As 2 [9,14,15]. While the inner hole band is gapped by about 200 meV below E F for both k z values, the band gap of the outer one varies from nearly 93 to 300 meV between Γ and Z.…”

Section: Resultssupporting

confidence: 63%

Angle-resolved photoemission observation of Mn-pnictide hybridization and negligible band structure renormalization in BaMn2As2 and BaMn2Sb2
Zhang¹,
Richard²,
Roekeghem³
et al. 2016
Phys. Rev. B
23
4
27
0
View full text Add to dashboard Cite

We performed an angle-resolved photoemission spectroscopy study of BaMn2As2 and BaMn2Sb2, which are isostructural to the parent compound BaFe2As2 of the 122 family of ferropnictide superconductors. We show the existence of a strongly kz-dependent band gap with a minimum at the Brillouin zone center, in agreement with their semiconducting properties. Despite the half-filling of the electronic 3d shell, we show that the band structure in these materials is almost not renormalized from the Kohn-Sham bands of density functional theory. Our photon energy dependent study provides evidence for Mn-pnictide hybridization, which may play a role in tuning the electronic correlations in these compounds.

show abstract

Synthesis and thermoelectric properties of BaMn2Sb2 single crystals

Cited by 32 publications

References 23 publications

Narrow Bandgap in β-BaZn₂As₂ and Its Chemical Origins

Narrow Bandgap in β-BaZn₂As₂ and Its Chemical Origins

Antiferromagnetism in semiconductingSrMn2Sb2andBaMn2Sb2single crystals

Angle-resolved photoemission observation of Mn-pnictide hybridization and negligible band structure renormalization in BaMn2As2 and BaMn2Sb2
Zhang¹,
Richard²,
Roekeghem³
et al. 2016
Phys. Rev. B
23
4
27
0
View full text Add to dashboard Cite

Contact Info

Product

Resources

About

Synthesis and thermoelectric properties of BaMn2Sb2 single crystals

Cited by 32 publications

References 23 publications

Narrow Bandgap in β-BaZn2As2 and Its Chemical Origins

Narrow Bandgap in β-BaZn2As2 and Its Chemical Origins

Antiferromagnetism in semiconductingSrMn2Sb2andBaMn2Sb2single crystals

Angle-resolved photoemission observation of Mn-pnictide hybridization and negligible band structure renormalization in BaMn2As2 and BaMn2Sb2Zhang1, Richard2, Roekeghem3 et al. 2016Phys. Rev. B234270View full textAdd to dashboardCite

Contact Info

Product

Resources

About

Narrow Bandgap in β-BaZn₂As₂ and Its Chemical Origins

Narrow Bandgap in β-BaZn₂As₂ and Its Chemical Origins

Angle-resolved photoemission observation of Mn-pnictide hybridization and negligible band structure renormalization in BaMn2As2 and BaMn2Sb2
Zhang¹,
Richard²,
Roekeghem³
et al. 2016
Phys. Rev. B
23
4
27
0
View full text Add to dashboard Cite