Atomic orbitals diagrams

Another way to represent this is to use orbital diagrams that look like atomic orbital diagrams. The same H2 molecule can be shown as follows in Figure 7.25 ... 

Draw atomic orbital diagrams representing the ground-state electron configuration for each of the following elements. 

For elements 1-36, there are two exceptions to the filling order as predicted from the periodic table. Draw the atomic orbital diagrams for the two exceptions and indicate how many unpaired electrons are present. 

The two lobes of the orbital may be indicated by open areas containing the signs of the wave function in the two areas, or they may be represented by filled and open areas which represent the positive and negative values of the wave function, respectively. In the remainder of the book the filled and open parts of atomic orbital diagrams are used to denote positive and negative signs of wave functions. 

The spatial orientations of the atomic orbitals of the hydrogen atom were described in terms of atomic orbital diagrams, based upon envelopes of i values. 

Table 1.5. Hybrid atomic orbitals. Diagram and description of most common hybrid orbitals...

Recognizing Correct and Incorrect Ground State and Excited State Atomic Orbital Diagrams... 

The atomic absorption spectrum for Na is shown in Figure 10.19 and is typical of that found for most atoms. The most obvious feature of this spectrum is that it consists of a few, discrete absorption lines corresponding to transitions between the ground state (the 3s atomic orbital) and the 3p and 4p atomic orbitals. Absorption from excited states, such as that from the 3p atomic orbital to the 4s or 3d atomic orbital, which are included in the energy level diagram in Figure 10.18, are too weak to detect. Since the... 

Figure 1.8 Polar diagrams for Is, 2p and 3d atomic orbitals showing the distributions of the angular wave functions...

Figure 7.14 Molecular orbital energy level diagram for first-row homonuclear diatomic molecules. The 2p, 2py, 2p atomic orbitals are degenerate in an atom and have been separated for convenience. (In O2 and F2 the order of

The electron configuration or orbital diagram of an atom of an element can be deduced from its position in the periodic table. Beyond that, position in the table can be used to predict (Section 6.8) the relative sizes of atoms and ions (atomic radius, ionic radius) and the relative tendencies of atoms to give up or acquire electrons (ionization energy, electronegativity). 

For many purposes, electron configurations are sufficient to describe the arrangements of electrons in atoms. Sometimes, however, it is useful to go a step further and show how electrons are distributed among orbitals. In such cases, orbital diagrams are used. Each orbital is represented by parentheses (), and electrons are shown by arrows written f or, depending on spin. 

To show how orbital diagrams are obtained from electron configurations, consider the boron atom (Z = 5). Its electron configuration is ls22s22p1. The pair of electrons in the Is orbital must have opposed spins (+j, or f j). The same is true of the two electrons in the 2s orbital. There are three orbitals in the 2p sublevel. The single 2p electron in boron could be in any one of these orbitals. Its spin could be either up or down. The orbital diagram is ordinarily written... 

With the next element, carbon, a complication arises. In which orbital should the sixth electron go It could go in the same orbital as the other 2p electron, in which case it would have to have the opposite spin, [. It could go into one of the other two orbitals, either with a parallel spin, f, or an opposed spin, Experiment shows that there is an energy difference among these arrangements. The most stable is the one in which the two electrons are in different orbitals with parallel spins. The orbital diagram of the carbon atom is... 

Orbital diagrams for atoms with five to ten electrons. Orbitals of equal energy are all occupied by unpaired electrons before pairing begins. 

Construct orbital diagrams for atoms of sulfur and iron. 

Give the symbdofthe atom with the following orbital diagram beyond argon. 

According to this model, a covalent bond consists of a pair of electrons of opposed spin within an orbital. For example, a hydrogen atom forms a covalent bond by accepting an electron from another atom to complete its Is orbital. Using orbital diagrams, we could write... 

Figure 2.14. The molecular orbitals of gas phase carbon monoxide, (a) Energy diagram indicating how the molecular orbitals arise from the combination of atomic orbitals of carbon (C) and oxygen (O). Conventional arrows are used to indicate the spin orientations of electrons in the occupied orbitals. Asterisks denote antibonding molecular orbitals, (b) Spatial distributions of key orbitals involved in the chemisorption of carbon monoxide. Barring indicates empty orbitals.5 (c) Electronic configurations of CO and NO in vacuum as compared to the density of states of a Pt(lll) cluster.11 Reprinted from ref. 11 with permission from Elsevier Science.

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