Calcium polonide

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Calcium polonide
Names
Preferred IUPAC name
Calcium polonide
Identifiers
3D model (JSmol)
ChemSpider
  • InChI=1S/Ca.Po/q+2;-2
    Key: NWHIVWOERKOURT-UHFFFAOYSA-N
  • [Ca+2].[Po-2]
Properties
CaPo
Molar mass 249 g·mol−1
Density 6.0 g/cm3
Structure [1]
Rock Salt (cubic)
Fm3m (No. 225)
a = 0.6514 nm
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Calcium polonide is an intermetallic compound with the chemical formula Ca Po . It is made up of calcium and polonium. Rather than being found in nature, the compound is entirely synthetic, and difficult to study, due to polonium's high vapor pressure, radioactivity, and easy oxidation in air.

Contents

Structure

At atmospheric pressure, it crystalizes in the cubic rock salt crystal structure. [1] At a high pressure of around 16.7 GPa, the structure is predicted to transform to the caesium chloride-type crystal structure. [2]

Electronic properties

Based on theoretical calculations, calcium polonide is predicted to be a semiconductor. [3]

See also

Related Research Articles

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Polonium is a chemical element; it has symbol Po and atomic number 84. A rare and highly radioactive metal with no stable isotopes, polonium is a chalcogen and chemically similar to selenium and tellurium, though its metallic character resembles that of its horizontal neighbors in the periodic table: thallium, lead, and bismuth. Due to the short half-life of all its isotopes, its natural occurrence is limited to tiny traces of the fleeting polonium-210 in uranium ores, as it is the penultimate daughter of natural uranium-238. Though longer-lived isotopes exist, such as the 124 years half-life of polonium-209, they are much more difficult to produce. Today, polonium is usually produced in milligram quantities by the neutron irradiation of bismuth. Due to its intense radioactivity, which results in the radiolysis of chemical bonds and radioactive self-heating, its chemistry has mostly been investigated on the trace scale only.

<span class="mw-page-title-main">Cubic crystal system</span> Crystallographic system where the unit cell is in the shape of a cube

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<span class="mw-page-title-main">Magnesium peroxide</span> Chemical compound

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<span class="mw-page-title-main">Heusler compound</span> Type of metallic alloy

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<span class="mw-page-title-main">A15 phases</span>

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<span class="mw-page-title-main">Polonium hydride</span> Chemical compound

Polonium hydride (also known as polonium dihydride, hydrogen polonide, or polane) is a chemical compound with the formula PoH2. It is a liquid at room temperature, the second hydrogen chalcogenide with this property after water. It is very unstable chemically and tends to decompose into elemental polonium and hydrogen. It is a volatile and very labile compound, from which many polonides can be derived. Additionally, it is radioactive.

<span class="mw-page-title-main">Polonide</span> Chemical compound

A polonide is a chemical compound of the radioactive element polonium with any element less electronegative than polonium. Polonides are usually prepared by a direct reaction between the elements at temperatures of around 300–400 °C. They are amongst the most chemically stable compounds of polonium, and can be divided into two broad groups:

<span class="mw-page-title-main">Magnesium polonide</span> Chemical compound

Magnesium polonide (MgPo) is a salt of magnesium and polonium. It is a polonide, a set of very chemically stable compounds of polonium.

<span class="mw-page-title-main">Sodium polonide</span> Chemical compound

Sodium polonide is a radioactive chemical compound with the formula Na2Po. This salt is a polonide, a set of very chemically stable compounds of polonium. Due to the difference in electronegativity (ΔEN) between sodium and polonium and the slight non-metallic character of polonium, it is intermediate between intermetallic phases and ionic compounds.

<span class="mw-page-title-main">Potassium polonide</span> Chemical compound

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The metallic elements in the periodic table located between the transition metals to their left and the chemically weak nonmetallic metalloids to their right have received many names in the literature, such as post-transition metals, poor metals, other metals, p-block metals and chemically weak metals. The most common name, post-transition metals, is generally used in this article.

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Oxybismuthides or bismuthide oxides are chemical compounds formally containing the group BiO, with one bismuth and one oxygen atom. The bismuth and oxygen are not bound together as in bismuthates, instead they make a separate presence bound to the cations (metals), and could be considered as a mixed bismuthide-oxide compound. So a compound with OmBin requires cations to balance a negative charge of 2m+3n. The cations will have charges of +2 or +3. The trications are often rare earth elements or actinides. They are in the category of oxypnictide compounds.

<span class="mw-page-title-main">Cobalt germanide</span> Chemical compound

Cobalt germanide (CoGe) is an intermetallic compound, a germanide of cobalt.

<span class="mw-page-title-main">Lanthanum phosphide</span> Chemical compound

Lanthanum phosphide is an inorganic compound of lanthanum and phosphorus with the chemical formula LaP.

References

  1. 1 2 Witteman, W. G.; Giorgi, A. L.; Vier, D. T. (1960). "The Preparation and Identification of Some Intermetallic Compounds of Polonium". The Journal of Physical Chemistry. 64 (4). American Chemical Society (ACS): 434–440. doi:10.1021/j100833a014. ISSN   0022-3654.
  2. Shi, Liwei; Wu, Ling; Duan, Yifeng; Hao, Lanzhong; Hu, Jing; Yang, Xianqing; Tang, Gang (2012). "Band structure, phase transition, phonon and elastic instabilities in calcium polonide under pressure: A first-principles study". Solid State Communications. 152 (22). Elsevier BV: 2058–2062. Bibcode:2012SSCom.152.2058S. doi:10.1016/j.ssc.2012.08.028. ISSN   0038-1098.
  3. Bhardwaj, Purvee; Singh, Sadhna (2015-06-09). "Phase transition and bulk properties of some polonide compounds: a comparative study". Phase Transitions. 88 (9). Informa UK Limited: 859–876. Bibcode:2015PhaTr..88..859B. doi:10.1080/01411594.2015.1020312. ISSN   0141-1594. S2CID   93331676.