Chemistry:Caesium sesquioxide

From HandWiki
Caesium sesquioxide
Identifiers
3D model (JSmol)
Properties
Cs4O6
Molar mass 627.616 g·mol−1
Appearance black powder[1]
Structure[1]
Pu
2
C
3
structure type (body-centered cubic)
I43d (no. 220)
a = 984.6 pm
Related compounds
Other cations
Rubidium sesquioxide
Related caesium oxides
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Caesium sesquioxide is a chemical compound with the formula Cs
2
O
3
or more accurately Cs
4
O
6
. It is an oxide of caesium containing oxygen in different oxidation states. It consists of caesium cations Cs+
, superoxide anions O
2
and peroxide anions O2−
2
. Caesium in this compound has an oxidation state of +1, while oxygen in superoxide has an oxidation state of −1/2 and oxygen in peroxide has an oxidation state of −1. This compound has a structural formula of (Cs+
)
4
(O
2
)
2
(O2−
2
)
.[1][2] Compared to the other caesium oxides, this phase is less well studied,[3] but has been long present in the literature.[4] It can be created by thermal decomposition of caesium superoxide at 290 °C.[5]

4 CsO
2
→ Cs
4
O
6
+ O
2

The compound is often studied as an example of a Verwey type charge ordering transition at low temperatures.[6][7][8] There were some theoretical suggestions that Cs
4
O
6
would be a ferromagnetic half metal,[9] but along with the closely related rubidium sesquioxide, experimental results found a magnetically frustrated system.[1] Below about 200 K, the structure changes to tetragonal symmetry.[10] Electron paramagnetic resonance and nuclear magnetic resonance measurements show a complicated low temperature magnetic behavior that depends on the orientation of the oxygen dimers and superexchange through the caesium atoms.[11]

References

  1. 1.0 1.1 1.2 1.3 Winterlik, Jürgen; Fecher, Gerhard H.; Jenkins, Catherine A.; Medvedev, Sergey; Felser, Claudia et al. (2009-06-09). "Exotic magnetism in the alkali sesquioxides Rb4O6 and Cs4O6". Physical Review B 79 (21): 214410. doi:10.1103/physrevb.79.214410. ISSN 1098-0121. Bibcode2009PhRvB..79u4410W. 
  2. https://sites.google.com/site/chempendix/oxidation
  3. Band, A.; Albu-Yaron, A.; Livneh, T.; Cohen, H.; Feldman, Y.; Shimon, L.; Popovitz-Biro, R.; Lyahovitskaya, V. et al. (2004-07-27). "Characterization of Oxides of Cesium". The Journal of Physical Chemistry B (American Chemical Society (ACS)) 108 (33): 12360–12367. doi:10.1021/jp036432o. ISSN 1520-6106. 
  4. Helms, Alfred; Klemm, Wilhelm (1939-08-29). "Über die Kristallstrukturen der Rubidium- und Cäsiumsesquioxyde" (in de). Zeitschrift für anorganische und allgemeine Chemie (Wiley) 242 (2): 201–214. doi:10.1002/zaac.19392420210. ISSN 0863-1786. 
  5. Merz, Patrick; Schmidt, Marcus; Felser, Claudia; Jansen, Martin (2017-03-24). "Thermo-analytical Investigations on the Superoxides AO2 (A = K, Rb, Cs), Revealing Facile Access to Sesquioxides A4O6". Zeitschrift für anorganische und allgemeine Chemie (Wiley) 643 (8): 544–547. doi:10.1002/zaac.201700013. ISSN 0044-2313. 
  6. Max Planck Society (2018-01-19). "Charge order and electron localization in a molecule-based solid". https://phys.org/news/2018-01-electron-localization-molecule-based-solid.html. 
  7. Adler, Peter; Jeglič, Peter; Reehuis, Manfred; Geiß, Matthias; Merz, Patrick; Knaflič, Tilen; Komelj, Matej; Hoser, Andreas et al. (2018-01-17). "Verwey-type charge ordering transition in an open-shell p -electron compound". Science Advances (American Association for the Advancement of Science (AAAS)) 4 (1): eaap7581. doi:10.1126/sciadv.aap7581. ISSN 2375-2548. PMID 29372183. Bibcode2018SciA....4.7581A. 
  8. Colman, Ross H.; Okur, H. Esma; Kockelmann, Winfried; Brown, Craig M.; Sans, Annette; Felser, Claudia; Jansen, Martin; Prassides, Kosmas (2019-10-21). "Elusive Valence Transition in Mixed-Valence Sesquioxide Cs4O6". Inorganic Chemistry (American Chemical Society (ACS)) 58 (21): 14532–14541. doi:10.1021/acs.inorgchem.9b02122. ISSN 0020-1669. PMID 31633914. 
  9. Attema, J J; Wijs, G A de; Groot, R A de (2007-04-05). "Spintronic materials based on main-group elements". Journal of Physics: Condensed Matter (IOP Publishing) 19 (16): 165203. doi:10.1088/0953-8984/19/16/165203. ISSN 0953-8984. Bibcode2007JPCM...19p5203A. https://pure.rug.nl/ws/files/6705863/2007JPhysAttema.pdf. 
  10. Okur, H. Esma; Colman, Ross H.; Ohishi, Yasuo; Sans, Annette; Felser, Claudia; Jansen, Martin; Prassides, Kosmas (2020-01-06). "Pressure-Induced Charge Disorder–Order Transition in the Cs4O6 Sesquioxide". Inorganic Chemistry (American Chemical Society (ACS)) 59 (2): 1256–1264. doi:10.1021/acs.inorgchem.9b02974. ISSN 0020-1669. PMID 31904961. 
  11. Arčon, D.; Anderle, K.; Klanjšek, M.; Sans, A.; Mühle, C.; Adler, P.; Schnelle, W.; Jansen, M. et al. (2013-12-10). "Influence of O2 molecular orientation on p-orbital ordering and exchange pathways in Cs4O6". Physical Review B (American Physical Society (APS)) 88 (22): 224409. doi:10.1103/physrevb.88.224409. ISSN 1098-0121. Bibcode2013PhRvB..88v4409A.