Sea of electrons

The simplest picture of a metallic conductor is one where we have a rigid lattice of metal (M) atoms, each of which has lost one or more electrons to form a surrounding sea of electrons. 

In Pauli s model, we still envisage a core of rigid cations (metal atoms that have lost electrons), surrounded by a sea of electrons. The electrons are treated as non-interacting particles just as in the Drude model, but the analysis is done according to the rules of quantum mechanics. 

In Pauli s model, the sea of electrons, known as the conduction electrons are taken to be non-interacting and so the total wavefunction is just a product of individual one-electron wavefuncdons. The Pauli model takes account of the exclusion principle each conduction electron has spin and so each available spatial quantum state can accommodate a pair of electrons, one of either spin. 

Figure 9.1 Id illustrates a simple model of bonding in metals known as the electron-sea model. The metallic crystal is pictured as an array of positive ions, for example, Na+, Mg2+. These are anchored in position, like buoys in a mobile sea of electrons. These electrons are not attached to any particular positive ion but rather can wander through the crystal. The electron-sea model explains many of the characteristic properties of metals ...

Sea of electrons, 304 Seaborg, Glenn T., 420 Second column of periodic table, 377 Second-row elements, bonding capacity. 281... 

FIGURE 1.53 A block of metal consists of an array of cations (the spheres) surrounded by a sea of electrons. The charge of the electron sea cancels the charges of the cations. The electrons of the sea are mobile and can move past the cations quite easily and hence conduct an electric current. 

Metallic solids, also called simply metals, consist of cations held together by a sea of electrons. 

The hypothetical metal jellium consists of an ordered array of positively charged metal ions surrounded by a structureless sea of electrons that behaves as a free electron gas (Fig. 6.13). 

Metals exist in definite crystal arrangement — cations surrounded by sea of electrons. ... 

Structural Unit ions cations surrounded by mobile "sea" of electrons atoms polar or nonpolar molecules... 

Metals are solid at room temperature, except for mercury. This tells us that the attractive forces between metal atoms are strong. The valence electrons of metal atoms can easily move from the free orbitals of one atom to another. These electrons that can move freely between atoms form an electron sea . An attractive force occurs between the negatively charged sea of electrons and the positively charged nuclei. Metal atoms are held together because of this attractive force. This is called the metallic bond. 

The Na atom has one half-filled (3s1) and three empty orbitals (3px, 3py, 3pz). The number of valence orbitals is greater than the number of valence electrons. In the solid state, sodium atoms are surrounded by other sodium atoms. Thus, the valence electron of the sodium atom in the 3s orbital can move to the empty orbitals (3px, 3py, 3pz) of neighbouring atoms. When each sodium valence electron behaves in this way a sea of electrons is built up around the sodium atoms (now positive ions, having lost a valence electron). 

We will discuss the first two types of bonding, ionic and covalent, in some depth. Metallic bonding is a topic that is very rarely encountered on the AP exam. Suffice it to say that metallic bonding is a bonding situation between metals in which the valence electrons are donated to a vast electron pool (sometimes called a "sea of electrons"), so that the valence electrons are free to move throughout the entire metallic solid. 

Metals consist of a regular array of metal cations surrounded by a sea of electrons. These electrons occupy the space between the cations, binding them together, but are able to move under the influence of an external field, thus accounting for the electrical conductivity of metals. 

Impurities in semiconductors, which release either free electrons or free holes (the absence of an electron in an otherwise filled sea of electrons), also give rise to optical properties at low energies below the minimum band gap (e.g., 1.1 eV for Si) that are characteristic of the Drude theory. Plasma frequencies for such doped semiconductors may be about 0.1 eV. 

The low ionization energies of elements at the lower left of the periodic table account for their metallic character. A block of metal consists of a collection of cations of the element surrounded by a sea of valence electrons that the atoms have lost (Fig. 1.42). For example, a piece of copper consists of a stack of Cu+ ions held together by a sea of electrons, each of which comes from one of the atoms in the sample. Only elements with low ionization energies—the members of the s block, the d block, the f block, and the lower left of the p block—can form metallic solids, because only they can lose electrons easily. 

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