caesium hydride

{{Chembox

| Verifiedfields = changed

| verifiedrevid = 458621197

| Name = Caesium hydride

| ImageFile = Caesium-hydride-unit-cell-3D-SF.png

| ImageSize = 200px

| ImageCaption = {{legend|rgb(52,12,92)|Caesium cation, {{chem2|Cs+}}}}{{legend|white|Hydrogen anion, {{chem2|H−}}}}

| IUPACName = Caesium hydride

| OtherNames = Cesium hydride

| SystematicName =

| Section1 = {{Chembox Identifiers

| CASNo_Ref = {{cascite|changed|??}}

| CASNo = 13772-47-9

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/Cs.H/q+1;-1

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = HXCOCQWMKNUQSA-UHFFFAOYSA-N

| PubChem = 139281

| ChemSpiderID = 122830

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| InChI= 1S/Cs.H/q+1;-1

| InChIKey= HXCOCQWMKNUQSA-UHFFFAOYSA-N

| SMILES= [H-].[Cs+]

}}

| Section2 = {{Chembox Properties

| Formula = CsH

| MolarMass = 133.91339 g/mol

| Appearance = White or colorless crystals or powder{{RubberBible86th|page=4.57}}

| MeltingPt= ~170 °C (decomposes)

| Density = 3.42 g/cm³

}}

| Section3 = {{Chembox Structure

| Coordination = Octahedral

| CrystalStruct = Face centered cubic

}}

| Section4 =

| Section5 =

| Section6 =

| Section8 = {{Chembox Related

| OtherAnions = {{ubl|CsF|CsCl|CsBr|CsI}}

| OtherCations = {{ubl|LiH|NaH|KH|RbH|Hydrides}}

}}

}}

Caesium hydride or cesium hydride is an inorganic compound of caesium and hydrogen with the chemical formula {{chem2|CsH|auto=1}}. It is an alkali metal hydride.

It was the first substance to be created by light-induced particle formation in metal vapor,{{cite journal| first1 = A. | last1 = Tam | first2 = G. | last2 = Moe | first3 = W. | last3 = Happer | title = Particle Formation by Resonant Laser Light in Alkali-Metal Vapor | journal = Phys. Rev. Lett. | year = 1975 | volume = 35 | pages = 1630–33 | doi = 10.1103/PhysRevLett.35.1630 | bibcode=1975PhRvL..35.1630T| issue = 24}} and showed promise in early studies of an ion propulsion system using caesium.{{cite web| last1 = Burkhart | first1 = J. A. | last2 = Smith | first2 = F. J. | title = Application of dynamic programming to optimizing the orbital control process of a 24-hour communications satellite | url = https://ntrs.nasa.gov/search.jsp?R=543868&id=2&qs=N%3D4294965816 | series = NASA Technical Report | date = November 1963}} It is the most reactive stable alkaline metal hydride of all. It is a powerful superbase and reacts with water extremely vigorously.

The caesium nucleus in CsH can be hyperpolarized through interactions with an optically pumped caesium vapor in a process known as spin-exchange optical pumping (SEOP). SEOP can increase the nuclear magnetic resonance (NMR) signal of caesium nucleus by an order of magnitude.{{cite journal| first1 = K. | last1 = Ishikawa | first2 = B. | last2 = Patton | first3 = Y.-Y. | last3 = Jau | first4 = W. | last4 = Happer | title = Spin Transfer from an Optically Pumped Alkali Vapor to a Solid | journal = Phys. Rev. Lett. | year = 2007 | volume = 98 | page = 183004 | doi = 10.1103/PhysRevLett.98.183004 | bibcode=2007PhRvL..98r3004I| issue = 18 | pmid=17501572|url=https://zenodo.org/record/1059117}}

It is very difficult to make caesium hydride in a pure form. Caesium hydride can be produced by heating caesium carbonate and metallic magnesium in hydrogen at 580 to 620 °C.{{Cite book|url=https://archive.org/details/in.ernet.dli.2015.153684|title=A Text Book Of Inorganic Chemistry Volume I The Alkali Metals And Their Congeners|last=A. Jamieson Walker|date=1924}}