Xenon electronic structure

The xenon atom can therefore be used as a delicate probe to determine the number of surrounding water molecules and their orientations. These results demonstrate the sensitivity of the easily polarizable xenon electronic structure to the electrostatic properties of its surrounding and the great potential for achieving accurate interpretations of magnetic resonance parameters from imaging experiments with hyperpolarized xenon. 

In xenon difluoride, the electronic structure shows three lone pairs around the xenon, and two covalent bonds to the two fluorine atoms hence it is believed that here xenon is using one p (doublepear) orbital to form two bonds ... 

The elements helium, neon, argon, krypton, xenon, and radon—known as the noble gases—almost always have monatomic molecules. Their atoms are not combined with atoms of other elements or with other atoms like themselves. Prior to 1962, no compounds of these elements were known. (Since 1962, some compounds of krypton, xenon, and radon have been prepared.) Why are these elements so stable, while the elements with atomic numbers 1 less or 1 more are so reactive The answer lies in the electronic structures of their atoms. The electrons in atoms are arranged in shells, as described in Sec. 3.6. (A more detailed account of electronic structure will be presented in Chap. 17.)... 

In this paper we present the first application of the ZORA (Zeroth Order Regular Approximation of the Dirac Fock equation) formalism in Ab Initio electronic structure calculations. The ZORA method, which has been tested previously in the context of Density Functional Theory, has been implemented in the GAMESS-UK package. As was shown earlier we can split off a scalar part from the two component ZORA Hamiltonian. In the present work only the one component part is considered. We introduce a separate internal basis to represent the extra matrix elements, needed for the ZORA corrections. This leads to different options for the computation of the Coulomb matrix in this internal basis. The performance of this Hamiltonian and the effect of the different Coulomb matrix alternatives is tested in calculations on the radon en xenon atoms and the AuH molecule. In the atomic cases we compare with numerical Dirac Fock and numerical ZORA methods and with non relativistic and full Dirac basis set calculations. It is shown that ZORA recovers the bulk of the relativistic effect and that ZORA and Dirac Fock perform equally well in medium size basis set calculations. For AuH we have calculated the equilibrium bond length with the non relativistic Hartree Fock and ZORA methods and compare with the Dirac Fock result and the experimental value. Again the ZORA and Dirac Fock errors are of the same order of magnitude. 

Both theory and experiment indicate that the electronic structures of the noble gases [helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn)] are especially nonreactive these atoms are said to contain filled shells (Table 2.1). Much of the chemistry of the elements present in organic molecules is understandable in terms of a simple model describing the tendencies of the atoms to attain such filled-shell conditions by gaining, losing, or, most importantly, sharing electrons. 

Xenon can act as a complex ligand to form M-Xe bonds, especially with gold, which exhibits significant relativistic effects in view of its electronic structure, as discussed in Section 2.4.3. Some gold-xenon complexes have been prepared and characterized, and their structures are shown in Fig. 17.5.7. 

The chemical and electrochemical characteristic properties of elements are determined by the electrons in the last outer shell. Elements with outer levels filled to completion, i. e. the rare gases (helium, neon, argon, crypton, xenon and radon), are noted for the great stability of their electronic structures atoms of such elements, known for their chemical inactivity, do not show any tendency to form molecules, neither in mutual bonds nor in bonds with other atoms. 

Xenon NMR spectroscopy was used to characterize xenon in Ca, Mg Ni, Ag, Cu, Zn, and Cd - exchanged Y and X zeolites. We report here some examples concerning the location of these cations and the effect of their charge and electronic structure. 

Since the first 29xe NMR study of xenon adsorbed on a zeolite, this technique has been shown to be of interest for the investigation of the distribution and the size of supported metal particles, the quantitative distribution of phases chemisorbed on these particles, the dimensions of the void spaces of zeolites, the detection of structure defects, the location of cations and the effect of electric fields they create [1,2], We report here some typical applications related to the study of the location and the electronic structure of the cations. 

Xanthocobalt—see Cobalt, nitropentaammine-Xenon, pentafluoro-lone electron pair structure, 50 Xenon, trifluoro-structure, 45 Xenon(IV) complexes six-coordinate compounds structure, 53 Xenon hexafluoride geometry, 37 stereochemistry, 74 X-ray diffraction cobalt ammines, 13 configuration, 16 crystal structure, 15 Xylenol orange metallochromic indicator, 557... 

The electronic structure of rare earth atoms can be described in terms of a core of filled shells equivalent to a xenon atom plus the following configuration... 

All neutral lanthanides, in their ground configuration, comprise the closed shell electronic structure of the noble gas xenon... 

The other elements of the zero group —neon, argon, krypton, xenon, and radon —are also chemically inert. The small tendency of these inert elements to form chemical compounds is similarly due to the great stability of their electronic structures. These extremely stable electronic structures are formed by 2, 10, 18, 36, 54, and 86 electrons about a nucleus. 

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