PDF Publication Title:
Text from PDF Page: 146
136 Ingo Krossing 7 Bonding...................................... 146 7.1 BondinginS42+with6pelectrons ..................... 147 7.2 BondinginS62+with10pElectrons .................... 147 7.3 BondinginS82+ ................................. 148 7.4 BondinginS192+................................. 150 8 Summary,Conclusion,andOutlook.................... 150 References........................................ 151 1 Introduction Elemental sulfur with its relatively high electronegativity of 2.4 (Allred- Rochow) is commonly used as an electron acceptor and thus as an oxidizing agent. Accordingly a plethora of structures of homoatomic sulfur anions Sn and Sn2 (n2) and derivatives thereof is known but only three sulfur cat- ions Snm+ (n2, m=1, 2) were characterized in the solid state and a few more are known in solution and in the gas phase. This is in part due to the high 1st and 2nd ionization energies of the sulfur homocycles that required the development of special experimental techniques to handle the thermody- namically stable but very reactive polysulfur cation salts in condensed phas- es. Notwithstanding these problems, the chemistry of the homoatomic sulfur cations emerged from being poorly understood laboratory curiosities to ful- ly understood and thoroughly examined textbook examples of fundamental interest to the chemistry of the elements [1]. 1.1 Historical Development The first written account of species which now have been accepted to be sul- fur cations dates back to 1804 when Bucholz [2] reported on the blue color obtained upon addition of elemental sulfur to freshly distilled oleum. The nature of these blue species gave rise to much speculation and is currently— almost 200 years later—still under investigation [3]. Considerable progress was made in sulfur cation chemistry in the late 1960s until the early 1980s. This was connected to the development of a facile synthesis of salts of sulfur cations with weakly basic (mainly) fluoroarsenate(V) and -antimonate(V) anions and the use of weakly basic solvents such as HF, HSO3F, oleum, SO2, and AsF3. The first structural information on sulfur cations dates back to 1971 when the solid state structure of S8(AsF6)2 containing the weakly transannularly bonded Cs symmetric S82+ dication was determined [4]. In 1980 the structures of square planar S42+ and irregular S192+ cations were elucidated by single crystal X-ray diffraction methods [5, 6]. However, the situation is less clear in solution and already 45 years ago it was noticed thatPDF Image | Topics in Current Chemistry
PDF Search Title:
Topics in Current ChemistryOriginal File Name Searched:
Elemental-Sulfur-und-Sulfur-Rich-Compounds-I.pdfDIY PDF Search: Google It | Yahoo | Bing
Sulfur Deposition on Carbon Nanofibers using Supercritical CO2 Sulfur Deposition on Carbon Nanofibers using Supercritical CO2. Gamma sulfur also known as mother of pearl sulfur and nacreous sulfur... More Info
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)