3p orbitals

In many crystals there is sufficient overlap of atomic orbitals of adjacent atoms so that each group of a given quantum state can be treated as a crystal orbital or band. Such crystals will be electrically conducting if they have a partly filled band but if the bands are all either full or empty, the conductivity will be small. Metal oxides constitute an example of this type of crystal if exactly stoichiometric, all bands are either full or empty, and there is little electrical conductivity. If, however, some excess metal is present in an oxide, it will furnish electrons to an empty band formed of the 3s or 3p orbitals of the oxygen ions, thus giving electrical conductivity. An example is ZnO, which ordinarily has excess zinc in it. 

Once the 2s and 2p orbitals are filled the next level is the 3s followed by the 3p 3py and 3p orbitals Electrons in these orbitals are farther from the nucleus than those in the 2s and 2p orbitals and are of higher energy... 

The He I (21.22 eV) specttum of argon is shown in Figure 8.6. The two peaks both result from the removal of an electron from the 3p orbital in the process ... 

The ground configuration of Ar is KL3s 3p, giving an inverted P /2 multiplet. The excited states involved in laser action involve promotion of an electron from the 3p orbital into excited As,5s,Ap,5p,3d,Ad,... orbitals. Similarly, excited states of Kr involved arise from promotion of an electron from the Ap orbital. In Ar the KL3s 3p configuration gives rise to 5, V, terms (see Section 7.1.2.3). Most laser transitions involve the core in one of the states and the promoted electron in the Ap orbital. 

Three LMTO envelopes were used with the tail energies -0.01 Ry, -1 Ry and -2.3 Ry. In the first two of them, s,p,d orbitals were included and in the last one only. s and p were used. It was necessary to treat the Ti 3p and 3-s states in the semi-core state, i.e. to do a so called 2-panel calculation. The basis set for the second panel consisted of 3-s, 3p, 3d orbitals on the Ti sites and 3-s, 3p orbitals on the Si sites. The same quality k-mesh was used in all calculations to ensure maximum cancellation of numerical errors and to obtain accurate energy differences. 

The orbitals in an atom are organized into different layers, or electron shells, of successively larger size and energy. Different shells contain different numbers and kinds of orbitals, and each orbital within a shell can be occupied by two electrons. The first shell contains only a single s orbital, denoted Is, and thus holds only 2 electrons. The second shell contains one 2s orbital and three 2p orbitals and thus holds a total of 8 electrons. The third shell contains a 3s orbital, three 3p orbitals, and five 3d orbitals, for a total capacity of 18 electrons. These orbital groupings and their energy levels are shown in Figure 1.4. 

The extra electron pairs in an expanded octet are accommodated by using d orbitals. The phosphorus atom (five valence electrons) in PC15 and the sulfur atom (six valence electrons) in SF6 make use of 3d as well as 3s and 3p orbitals ... 

The UPS spectra (not shown here) recorded upon Al deposition onto the conjugated thiophene systems shows only small visible changes in the positions of the peaks in the spectra [84]. The main effect is a rapid decrease in intensity, which indicates that a metallic overlayer is formed since the cross-sections for the Al(3p) or Al(3s) are much lower than for the C(2p) or S(3p) orbitals. This is consistent with the Al(2p) XPS spectra discussed above. 

The electron configuration in the valence orbitals of the sulfur atom (3s 3p4) suggests that it will form two covalent bonds by making use of two half-filled 3p orbitals. This is, in fact, observed in the molecule S8, which is present in the common forms of solid sulfur. The S8 molecules assume the form of a puckered ring, as shown in Figure 20-3. As with the phosphorus, the stability of this crystalline form of sulfur is due to van der Waals forces between discrete molecules. 

The electronic structure of the chlorine atom (3s-3p ) provides a satisfactory explanation of the elemental form of this substance also. The single half-filled 3p orbital can be used to form one covalent bond, and therefore chlorine exists as a diatomic molecule. Finally, in the argon atom all valence orbitals of low energy are occupied by electrons, and the possibility for chemical bonding between the atoms is lost. 

The percentage of the spin-density on the 3s and 3p orbitals of the sulfur has been recalculated using the atomic parameters given by J. R. Morton and K. F. Preston, J. Magn. Reson., 30, 577 (1978). 

This plot shows the radial distribution function of the 3s and 3p orbitals of a hydrogen atom. Identify each curve and explain how you made your decision. 

The plot with the most electron density closest to the origin (0, 0—the nucleus) arises from the s-orbital. Curve (b) corresponds to the 3s-orbital curve (a) corresponds to the 3p-orbital. 

The frontier orbital of an electropilic reagent, HCl, is the LUMO or the antibonding orbital of the cr bond. The Is orbital energy (-13.6 eV) of hydrogen atom is higher than the 3p orbital energy (-15.1 eV) of chlorine atom [5]. The main component of is Is which mixes 3p out of phase. 

The n orbitals on the two CO molecules interact with the same lobe of a vacant 3p orbital on a metal atom in the model for the acute angle coordination, and with different lobes for the obtuse angle coordination (Scheme 29b). Cychc orbital interaction occurs between the occupied 3s orbital and the vacant 3p orbitals on M and the n orbitals, n, and n, of the CO molecules (Scheme 29c). The phase is continuous for the same lobe interaction and discontinuous for the different lobe interaction (Scheme 29d, cf. Scheme 4). The acute-angle coordination is favored. 

Radical IV can be considered as a unique phosphorus radical species. Reduction of the parent macrocycle with sodium naphtalenide in THF at room temperature gave a purple solution. The FPR spectrum displayed a signal in a 1 2 1 pattern, with flp(2P)=0.38 mT. DFT calculations on radical IV models indicated a P-P distance of 2.763 A (P - P is3.256 A in the crystal structure of the parent compound and the average value of a single P-P bond is 2.2 A). According to the authors, the small coupling constant arises from the facts that the principal values of the hyperfine tensor are of opposite sign and that the a P P one electron bond results from overlap of two 3p orbitals [88]. 

As described in several review articles [409,452-454] and books [10,13,15], this is basically due to the inherent features of the d -p bond in phosphazenes, which allows the permanent overlapping of the 2pj orbital of the skeletal nitrogens with any one of the 3p orbitals of the phosphorus atoms [455]. Such a high chain flexibihty generated very low glass transition temperatures in these polymers, which can reach values of about -100 °C when suitable flexible substituent groups (e.g. n-butanol) are present on the skeletal phosphorus [274]. 

Ph CASSCF wave function resulting from all arrangements of the 3s and 3p electrons in the 3s and 3p orbitals. ... 

An atomic orbital is designated by its and / values, such as Is, 4p, 3d, and so on. When / > 0, there is more than one orbital of each designation three p orbitals, five d orbitals, and so on. When an electron occupies any orbital, its spin quantum number, lit, can be either + or -. Thus, there are many sets of valid quantum numbers. An electron in a 3p orbital, for example, has six valid sets of quantum numbers n = 3, / = 1, m =+1, j — -2 / —i — — 1... 

As Increases, the detailed shapes of the p orbitals become more complicated (the number of nodes increases, just as for s orbitals). Nevertheless, the directionality of the orbitals does not change. Each p orbital is perpendicular to the other two in its set, and each p orbital has its lobes along its preferred axis, where electron density is high. To an approaching atom, therefore, an electron in a 3p orbital presents the same characteristics as one in a 2p orbital, except that the 3p orbital is bigger. Consequently, the shapes and relative orientations of the 2p orbitals in Figure 7-22 represent the prominent spatial features of all p orbitals. 

C07-0082. Shown beiow are electron density pictures and electron density plots for the Is, 2s, 2p, and 3p orbitals. Assign the various depictions to their respective orbitals. 

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