Strontium hexaboride
| Strontium boride | ||
|---|---|---|
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| Other names strontium hexaboride | ||
| Identifiers | ||
| CAS number | 12046-54-7  | |
| PubChem | 6336904 | |
| EC number | 234-969-8 | |
| Jmol-3D images | {{#if:[B].[B].[B].[B].[B].[B].[Sr]|Image 1 | |
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| Properties | ||
| Molecular formula | SrB6 | |
| Molar mass | 152.49 g/mol | |
| Appearance | black crystalline powder | |
| Density | 3.39 g/cm3, solid (15.0°C) | |
| Melting point | 2,235 °C; 4,055 °F; 2,508 K | |
| Solubility in water | insoluble | |
| Structure | ||
| Crystal structure | Cubic | |
| Space group | Pm3m ; Oh | |
| Hazards | ||
| EU classification | not listed | |
| NFPA 704 |
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(verify) (what is: / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa) | ||
| Infobox references | ||
Strontium boride (SrB6) is an inorganic compound. At room temperature, it appears as a crystalline black powder.[1] Closer examination reveals slightly translucent dark red crystals capable of scratching quartz.[2] It is very stable and has a high melting point and density. Although not thought to be toxic, it is an irritant to the skin, eyes, and respiratory tract.[1]
Magnetism
Strontium boride, along with other alkali-earth metal borides, has been shown to exhibit weak ferromagnetism at low temperatures.[3] This is thought by some to be caused by slight impurities or aberrations in the crystal lattice,[4][5] while others suggest different explanations are needed.[6] Strontium boride has also been examined for semiconducting properties at lower temperatures.[7]
Preparation
In his book The Electric Furnace, Henri Moissan describes an early synthesis of strontium boride by mixing strontium borate, aluminum, and carbon in an electric furnace.[2] Alternatively, a solid-phase synthesis of strontium boride can be carried out by reacting two moles of strontium carbonate with three moles of boron carbide and one mole of carbon inside a vacuum furnace.[8]
Uses
Strontium boride is used in insulation and nuclear control rods.[8] A recent patent filed for aircraft windows uses SrB6 nanoparticles in a transparent acrylic sheet. The IR-absorbing properties of these nanoparticles prevents the transmittance of infrared wavelengths while still allowing the transmittance of visible light.[9]
References
- ↑ 1.0 1.1 http://www.espimetals.com/msds%27s/strontiumboride.pdf
- ↑ 2.0 2.1 Moissan, Henri. The Electric Furnace.
- ↑ D. P. Young, D. Hall, M. E. Torelli, Z. Fisk, J. L. Sarrao, J. D. Thompson, H. R. Ott, S. B. Oseroff, R. G. Goodrich, and R. Zysler. High-temperature weak ferromagnetism in a low-density free-electron gas. Nature (London), 397, 412 (1999).
- ↑ Shang, S., & Liu, Z. "Thermodynamics of the B–Ca, B–Sr, and B–Ba systems: Applications for the fabrications of CaB6, SrB6, and BaB6 thin films". Applied Physics Letters, 2007, 90, 091914-1. Retrieved April 30, 2009, doi:10.1063/1.2710081
- ↑ J. L. Gavilano, B. Ambrosini, H. R. Ott, D. P. Young, Z. Fisk, "Low-temperature NMR studies of SrB6", Physica B: Condensed Matter, Volumes 281–282, 1 June 2000, Pages 428–429, ISSN 0921-4526, doi:10.1016/S0921-4526(99)01197-7 (http://www.sciencedirect.com/science/article/B6TVH-400WKV6-68/2/9b3bc29604aac16dd96856e9c7aab187)
- ↑ Dorneles, L., Venkatesan, M., Moliner, M., Lunney, J., & Coey, J. "Magnetism in thin films of CaB6 and SrB6". Applied Physics Letters, 2004, 85, 6377–6379. Retrieved April 30, 2009, doi:10.1063/1.1840113
- ↑ H. R. Ott, M. Chernikov, E. Felder, L. Degiorgi, E. G. Moshopoulou, J. L. Sarrao, Z. Fisk. Structure and low temperature properties of SrB6. Z. Phys. B, 1997, 102, 337–345.
- ↑ 8.0 8.1 Shu-Qi Zheng, Zeng-Da Zou, Guang-Hui Min, Hua-Shun Yu, Jian-De Han, Wei-Ti Wang. "Synthesis of strontium hexaboride powder by the reaction of strontium carbonate with boron carbide and carbon". Journal of Materials Science Letters, 2002, 21, 313–315.
- ↑ "United States Patent Application 20090093578". Retrieved 2009-05-05.
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