Cadmium(I) tetrachloroaluminate: Difference between revisions

| Watchedfields = changed

| verifiedrevid = 428770430

|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo = 103823-00-3

| SMILES = [Cd+][Cd+].Cl[Al-](Cl)(Cl)Cl.Cl[Al-](Cl)(Cl)Cl

| StdInChI=1S/2Al.2Cd.8ClH/h;;;;8*1H/q2*+3;2*+1;;;;;;;;/p-8

| StdInChIKey=MVYUNQSYEKWWLE-UHFFFAOYSA-F

}}

|Section2={{Chembox Properties

| Formula = {{chem2|Cd2[AlCl4]2}}

| MolarMass = 562.4123 g/mol

| Appearance = white crystal

| MeltingPt = 227 ° (decomp){{cln|reason=WHAT??? The unit of measurement of melting point is not a degree, because melting point is not an angle, but a temperature! Do you mean degrees Fahrenheit or degrees Celsius??? I cannot read your mind, sorry!|date=April 2023}}

|Section3={{Chembox Hazards

| AutoignitionPt =

| REL = Ca<ref name=PGCH>{{PGCH|0087}}</ref>

| PEL = [1910.1027] TWA 0.005 mg/m³ (as Cd)<ref name=PGCH/>

| IDLH = Ca [9 mg/m³ (as Cd)]<ref name=PGCH/>}}

'''Cadmium(I) tetrachloroaluminate''' is the [[inorganic compound]] with the formula {{chem2|Cd2[AlCl4]2}}, a [[tetrachloroaluminate]] of [[cadmium|cadmium(I)]]. It was the first compound reported (1961) that contained cadmium in the +1 oxidation state and features a cadmium&ndash;cadmium bond.

{{chem2|Cd2[AlCl4]2}} was originally prepared by dissolving Cd metal in molten [[cadmium chloride|{{chem2|CdCl2}}]] followed by the addition of [[aluminium trichloride|{{chem2|AlCl3}}]].<ref>{{Cite journal|last1=Corbett|first1=J. D.|last2=Burkhard|first2=W. J.|last3=Druding|first3=L. F.|date=January 1961|title=Stabilization of the Cadmium(I) Oxidation State. The System Cd-Cd{{su|b=2|p=1}}(AlCl{{su|b=4}}){{su|b=2}}&ndash;Cd{{su|p=2}}(AlCl{{su|b=4}}){{su|b=2}}|journal=Journal of the American Chemical Society|volume=83|issue=1|pages=76–80|doi=10.1021/ja01462a016}}</ref>

:{{chem2|CdCl2 + Cd → Cd2Cl2}}

:{{chem2|Cd2Cl2 + 2 AlCl3 → Cd2[AlCl4]2}}

Subsequent studies of the [[Raman spectroscopy|Raman]] vibrational spectrum indicated the presence of a cadmium&ndash;cadmium bond,<ref>{{Cite journal|last1=Corbett|first1=J. D.|date=Aug 1962|title=The Cadmium(I) Ion Cd{{su|b=2|p=2+}}. Raman Spectrum and Relationship to Hg{{su|b=2|p=2+}}|journal=Inorganic Chemistry|volume=1|issue=3|pages=700–703|doi=10.1021/ic50003a051}}</ref> which was confirmed by two separate X-ray diffraction studies of single crystals.<ref name="Faggiani">{{Cite journal|last1=Faggiani|first1=R.|author2=Ronald J. Gillespie|author3=John E. Vekris|year=1986|title=The cadmium(I) ion, Cd{{su|b=2|p=2+}}; X-ray crystal structure of {{chem|Cd|2|(AlCl|4|)|2}}|journal=Journal of the Chemical Society, Chemical Communications|volume=1986|issue=7|pages=517–518|doi=10.1039/C39860000517}}</ref><ref name="Meyer">{{Cite journal|last=Staffel|first=T.|author2=Dr. Gerd Meyer|year=1987|title=Synthesis and crystal structures of {{chem|Cd[AlCl|4|]|2|}} and {{chem|Cd|2|[AlCl|4|]|2|}}|journal=Zeitschrift für anorganische und allgemeine Chemie|volume=548|issue=5|pages=45–54|doi=10.1002/zaac.19875480505}}</ref><!-- <ref name = "Meyer">Synthesis and crystal structures of Cd[AlCl₄]₂ and Cd₂[AlCl₄]₂ Staffel T, Meyer G., Zeitschrift für anorganische und allgemeine Chemie, 548, 5, 45 - 54, {{doi|10.1002/zaac.19875480505 }}</ref> --> The compound can therefore be compared to mercury(I) (mercurous) compounds (such as [[mercury(I) chloride]]), which contain {{chem2|Hg2(2+)}}. The {{chem2|Cd\sCd}} [[single bond]]s are part of [[ethane]]-like {{chem2|Cd2Cl6}} units sharing vertices with {{chem2|AlCl4}} units, with a {{chem2|Cd\sCd}} bond length reported as 257.6 pm<ref name="Faggiani" /> or 256.1pm.<ref name="Meyer" />

{{chem2|Cd2[AlCl4]2}} is [[diamagnetic]]. It contains no unpaired electrons and reacts readily with water disproportionating to give Cd metal and {{chem2|Cd(2+)}}.[[File:Cadmium(I)-tetrachloroaluminate-xtal-1987-Cd-coordination-CM-3D-ellipsoids.png|left|thumb|200x200px|[[Thermal ellipsoid]] plot of a {{chem2|Cd2Cl6}} unit]]

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