Atomic magnesium

A solution of 6.3 g (0.9 moles) ethoxyacetylene in 50 ml ether is added dropwise during 30 min to a Grignard reagent prepared from 2.18 g (90 mg-atoms) magnesium and 9.81 g (90 mmoles) ethyl bromide. The reaction mixture is stirred for 1 hr at room temperature and then a solution of 3 g (9 mmoles) 3) -acetoxyandrost-5-en-I7-one in 50 ml dry ether is added dropwise. The mixture is refluxed for 1 hr and after cooling to 0° poured into 100 ml of an aqueous ammonium chloride solution. The aqueous solution is extracted with ether, and the organic extract is washed with ammonium chloride solution and water, dried, and evaporated. The residue is chromatographed on 130 g alumina (activity III). Elution with petroleum ether-benzene (1 1) yields, after crystallization from acetone-hexane, 1.27 g (35%) 3j5-acetoxy-17a-ethoxyethynylandrost-5-en-17) -ol mp 138-139° Ho -122°. 

A Grignard solution is prepared from 1.35 g (56 mg-atoms) magnesium, 3.7 ml (8.4 g, 59 mmoles) methyl iodide and 47 ml dry ether. After addition of 80 ml of dry tetrahydrofuran the solvent is removed by distillation until the boiling point reaches 62°. Additions of 0.27 g (2.7 mmoles) of cuprous... 

Figure 4 Effect of configuration interaction on some of the states of atomic magnesium.

The larger atoms, magnesium, have ligancy 16 (12 Cu and 4 Mg), as seen in Figure 11-13. This increase in ligancy for magnesium, relative to that (12) for the element, and the assumption of icosahedral coordination by copper cause a decrease in volume of the compound relative to the elements. The volume decrease is 6.7 percent. A part of it may be the result of electron transfer (Sec. 11-12), but similar decreases are found in general for icosahedral structures. 

Three widely used distribution equations, discussed by Bevans (JL), include the Rosin-Rammler (7L) and Nukiyama-Tanasawa (6L) equations as well as the log-probability equation. A fourth relationship, the upper-limit equation of Mugele and Evans (5L), is also discussed. Hawthorne and Stange also discuss the Rosin-Rammler relationship (4L, 8L). An excellent analysis of distributions is given by Dubrow (SL), who has studied atomized magnesium powders. 

A.G. Kochur, D. Petrini, E.P. da Silva, 2s-photoionisation of atomic magnesium Shake processes and Coster-Kronig radiationless decay, A A 365 (2001) 248. 

An experiment is said to be, within a certain theoretical framework, perfect or complete if from different experimental observations complementary information can be obtained which finally allows the determination of all matrix elements involved and, therefore, all possible observables. This will be illustrated for 2p photoionization in atomic magnesium (ground state electron configuration ls22s22p63s2). 

Figure 5.8 Angular distribution parameter / 2p for 2p photoionization in atomic magnesium as a function of photon energy. Experimental data points with error bars. Theoretical data (adapted to the experimental threshold for 2p ionization 2s - np resonances between 94 and 97 eV photon energy omitted) full curve, RRPA results [DMa83] within uncertainties of the drawing the saipe result is obtained in the MBPT approach [Alt89] broken curve, HF(1P) results [V6188] chain curve, Herman-Skillman results [DSa73]. From [KHL92],...

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