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Tellurium single crystal 52Te127.60
Tellurium was discovered in1783 by Baron Franz Joseph Müller von Reichenstein at Sibiu, Romania.
[Latin: tellus = earth]
French: tellure
German: tellur
Italian: tellurio
Spanish: teluro
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Description: Tellurium is a silvery-white, metallic-looking in bulk, but is usually obtained as a dark grey powder. It is a semi-metal. Tellurium burns in air or oxygen, is unaffected by water or HCl, but dissolves in HNO3. It is used in alloys to improve machinability, in electronics, and in catalysts.
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Metal single crystal properties
| State: |
Single crystal |
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| Crystal structure: |
Hexagonal |
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| Production method: |
Czochralski |
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| Standard size: |
diameter 10mm
thickness 1-2mm |
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| Orientation: |
(0001), (1100) and (11-20) |
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| Orientation accuracy: |
<2°, <1°, <0.5° or <0.25° |
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| Polishing: |
as cut, one or two sides polished |
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| Roughness of surface: |
<0.03µm |
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| Purity: |
99.999% |
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| Typical analysis (ppm): |
Ag < 0.010
Al < 0.030
B < 0.010
Bi < 0.005
Co < 0.005
Cr < 0.005
Cu < 0.015
Fe < 0.030
In < 0.010
Mg < 0.010 |
Mn < 0.005
Na < 0.050
Ni < 0.010
Pb < 0.015
S < 0.030
Si < 0.050
Sn < 0.020
Ti < 0.005
Tl < 0.005
Zn < 0.030
Te balance |
Further Materials properties
| Crystal structure: |
(cell dimensions/pm), space group
hexagonal (a=445.65, c=592.68), P3121 or P3221
High pressure forms: (a=420.8, c=1203.6), R3m; (a=460.3, c=382.2), R3m |
| X-ray diffractions mass absorption coefficients: |
CuKa 282 (µ/r) / cm2g-1
MoKa 35.0 (µ/r) / cm2g-1
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| Neutron scattering length: |
0.580 b/10-12 cm |
| Thermal neutron capture cross-section: |
4.7 sa / barns |
| Density: |
6.24 g/cm3 |
| Melting point: |
449.55 °C / 722.7 °K |
| Boiling point: |
989.85 °C / 1263.0 °K |
| Molar volume: |
20.45 cm3 |
| Thermal conductivity: |
2.35 [300 K] Wm-1K-1 |
| Coefficient of linear thermal expansion: |
16.75 x 10-6 K-1 |
| Electrical resistivity: |
4.36x10-3 [298 K] Wm |
| Mass magnetic susceptibility: |
-3.9 x 10-9(s) kg-1m3 |
| Young's modulus: |
47.1 GPa |
| Rigidity modulus: |
16.7 GPa |
| Bulk modulus: |
n.a. GPa |
| Poisson's ratio: |
0.16 - 0.3 GPa |
| Radii: |
Te3+ 56; Te4+ 97; Te2- 211; atomic 143; covalent 137; van der Waals 220 |
| Electronegativity: |
2.1 (Pauling); 2.01 (Allred); 5.49 eV (absolute) |
| Effective nuclear charge: |
6.95 (Slater); 10.81 (Clementi); 13.51 (Froese-Fischer) |
| Number of Isotopes (incl. nuclear isomers): |
39 |
| Issotope mass range: |
108 -> 137 |
Biological data
| Biological role: |
none |
| Toxicity |
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| Toxic intake: |
Elemental tellurium has low toxicity but unpleasant side effects, producing extremely unpleasant breath and body odour. |
| Lethal intake: |
2 g of sodium tellurite has proved fatal to a human. LD50 (Te metal, oral, rat)= 83 mg kg-1 |
| Hazards: |
Tellurium compounds are toxic by ingestion and intravenous routes. They are also considered to be experimental tetratogens. |
| Level in humans |
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| Blood: |
0.0055 mg dm-3 |
| Bone: |
n.a. |
| Liver: |
0.014 p.p.m. |
| Muscle: |
0.017 p.p.m. |
| Daily dietary intake : |
c. 0.6 mg |
Total mass of element in average
[70 kg] person: |
c. 0.7 mg |
Geological data
| Minerals: |
Many minerals are known, and aluminium is present in many other minerals |
| Mineral |
Formula |
Density |
Hardness |
Crystal apperance |
| Sylvanite |
AgAuTe4 |
8.16 |
1.5 - 2 |
mon., met. grey |
| Tellurite |
TeO2 |
5.90 |
2 |
orth., sub-adamantine white |
| Chief ore: |
none mined as such. Tellurium is obtained from the anode slime of copper refining.
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| World production: |
215 tonnes/year |
| Main mining areas: |
Sylvanite in Australia, USA and Romania |
| Reserves: |
n.a. |
| Specimen: |
available as granules, ingots, pieces or powder. DANGER !
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| Abundances |
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| Sun: |
n.a. |
| Earth's crust: |
c. 0.005 p.p.m. |
| Seawater: |
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| Atlantic surface: |
1.6 x 10-7 p.p.m. |
| Atlantic deep: |
1.9 x 10-7 p.p.m. |
| Pacific surface: |
1.9 x 10-7 p.p.m. |
| Pacific deep: |
1.7 x 10-7 p.p.m. |
| Residence time:: |
n.a. |
| Classification: |
scavenged |
| Oxidation state: |
IV and VI; mainly VI |
Other sizes and specifications on request
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