Plumbane

Until recently, it was uncertain whether plumbane had ever actually been synthesized,Cotton, F. A.; Wilkinson, G.; Murillo, C. A.; Bochman, M. Advanced Inorganic Chemistry. Wiley: New York, 1999 although the first reports date back to the 1920s{{cite journal | doi = 10.1002/cber.19200530915 | pages = 1693–1710 | title = Über Bleiwasserstoff | year = 1920 | last1 = Paneth | first1 = Fritz | last2 = Nörring | first2 = Otto | journal = Berichte der Deutschen Chemischen Gesellschaft (A and B Series) | volume = 53 | issue = 9| url = https://zenodo.org/record/1426681 }} and in 1963, Saalfeld and Svec reported the observation of {{chem|PbH|4|+}} by mass spectrometry.{{cite journal | doi = 10.1021/ic50005a014| pages= 46–50 | title = The Mass Spectra of Volatile Hydrides. I. The Monoelemental Hydrides of the Group IVB and VB Elements | year = 1963 | last1 = Saalfeld | first1 = Fred E. | last2 = Svec | first2 = Harry J. | journal = Inorganic Chemistry | volume = 2}} Plumbane has repeatedly been the subject of Dirac–Hartree–Fock relativistic calculation studies, which investigate the stabilities, geometries, and relative energies of hydrides of the formula MH{{sub|4}} or MH{{sub|2}}.{{cite journal | doi =10.1016/0009-2614(74)85085-2| pages= 534–539 | title =Relativistic and non-relativistic Hartree-Fock one-centre expansion calculations for the series CH{{sub|4}} to PbH{{sub|4}} within the spherical approximation | year =1974 | last1 =Desclaux | first1 =J. P. | last2 =Pyykko | first2 =P. | journal =Chemical Physics Letters | volume =29 | issue =4| bibcode= 1974CPL....29..534D }}{{cite journal | pages= 336–337 | doi =10.1038/266336a0 | title= Dirac–Fock one-centre calculations show (114)H{{sub|4}} to resemble PbH{{sub|4}} | year= 1977 | last1= Pyykkö | first1= P. | last2= Desclaux | first2= J. P. | journal= Nature | volume= 266 | issue= 5600| bibcode =1977Natur.266..336P | s2cid =4183019 }}

Plumbane is an unstable colorless gas and is the heaviest group IV hydride;CRC Handbook of Chemistry and Physics [http://www.hbcpnetbase.com/ Online Edition.] and has a Tetrahedral molecular geometry with an equilibrium distance between lead and hydrogen of 1.73 Å.{{cite journal | doi =10.1007/BF01134864 | pages=405–416 | title =Relativistic all-electron molecular Hartree-Fock-Dirac-(Breit) calculations on CH{{sub|4}}, SiH{{sub|4}}, GeH{{sub|4}}, SnH{{sub|4}}, PbH{{sub|4}} | year =1992 | last1 =Visser | first1 =O. | last2 =Visscher | first2 =L. | last3 =Aerts | first3 =P. J. C. | last4 =Nieuwpoort | first4 =W. C. | journal =Theoretica Chimica Acta | volume =81 | issue =6| s2cid=97874625 }} By weight, plumbane is 1.91% hydrogen and 98.09% lead. In plumbane, the formal oxidation states of hydrogen and lead are +1 and −4, respectively, because the electronegativity of lead(IV) is higher than that of hydrogen. The stability of hydrides MH{{sub|4}} (M = C–Pb) decreases as the atomic number of M increases.

Early studies of PbH{{sub|4}} revealed that the molecule is unstable as compared to its lighter congeners silane, germane, and stannane.{{cite journal | doi =10.1002/qua.20142 | pages=940–949 | title =Relativistic and electron correlation effects for molecules of heavy elements: Ab initio fully relativistic coupled-cluster calculations for PbH{{sub|4}} | year =2004 | last1 =Malli | first1 =Gulzari L. | last2 =Siegert | first2 =Martin | last3 =Turner | first3 =David P. | journal =International Journal of Quantum Chemistry | volume =99 | issue =6}} It cannot be made by methods used to synthesize GeH{{sub|4}} or SnH{{sub|4}}.

In 1999, plumbane was synthesized from lead(II) nitrate, Pb(NO{{sub|3}}){{sub|2}}, and sodium borohydride, NaBH{{sub|4}}.{{cite journal | last1 = Krivtsun | first1 = V. M. | last2 = Kuritsyn | first2 = Y. A. | last3 = Snegirev | first3 = E. P. | year = 1999 | title = Observation of IR absorption spectra of the unstable PbH{{sub|4}} molecule | url = http://www.isan.troitsk.ru/dms/tdl/publ/1999os_en.pdf | journal = Opt. Spectrosc. | volume = 86 | issue = 5 | pages = 686–691 | bibcode = 1999OptSp..86..686K | access-date = 2012-12-31 | archive-url = https://web.archive.org/web/20160304112423/http://www.isan.troitsk.ru/dms/tdl/publ/1999os_en.pdf | archive-date = 2016-03-04 | url-status = dead }} A non-nascent mechanism for plumbane synthesis was reported in 2005.{{cite journal | pmid =16395924 | year =2005 | last1 =Zou | first1 =Y | last2 =Jin | first2 =FX | last3 =Chen | first3 =ZJ | last4 =Qiu | first4 =DR | last5 =Yang | first5 =PY | title =Non-nascent hydrogen mechanism of plumbane generation | volume =25 | issue =10 | pages =1720–3 | journal =Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu}}

In 2003, Wang and Andrews carefully studied the preparation of PbH{{sub|4}} by laser ablation and additionally identified the infrared (IR) bands.{{cite journal | doi =10.1021/ja029862l | pages=6581–6587 | title =Infrared Spectra of Group 14 Hydrides in Solid Hydrogen: Experimental Observation of PbH{{sub|4}}, Pb{{sub|2}}H{{sub|2}}, and Pb{{sub|2}}H{{sub|4}} | year =2003 | last1 =Wang | first1 =Xuefeng | last2 =Andrews | first2 =Lester | journal =Journal of the American Chemical Society | volume =125 | issue =21 | pmid =12785799}}

Congeners of plumbane include:

• Methane, CH{{sub|4}}
• Silane, SiH{{sub|4}}
• Germane, GeH{{sub|4}}
• Stannane, SnH{{sub|4}}

{{reflist}}

{{Lead compounds}}

{{Hydrides by group}}

Category:Metal hydrides

Category:Lead compounds