Valence band- conduction band- valence electrons energy gap, Electrical Engineering

Assignment Help:

Explain the terms: valence band, conduction band, valence electrons, and energy gap with the help of suitable diagrams.

Valence Electrons: The electrons in the outermost orbit are termed as valence electrons, because these electrons are fixed into the outer orbit along with the neighbouring atom in a crystal. Such electrons being far away from nucleus possess least binding energy and they are easily influenced by external influences. An extremely little energy is needed to free them by their parent atoms. While the valence electrons of an atom are less than four, the material is generally a metal or a conductor. While the number of electrons in the outermost orbit is more than four, the material is generally an insulator. While the number of valence electrons in an atom is accurately four, the material is a semi-conductor.

Conduction Band: This shows a larger group of permissible energy levels. The orbits into the conduction band are extremely large and an electron in that band experiences almost negligible nucleus attraction. Actually an electron in the conduction band does not belong to any specific atom and this move randomly during the solid. Therefore these electrons in the conduction band are termed as free electrons. When any material has empty conduction band, therefore no conduction band is possible.

665_energy gap.png

Valence Band: This represents the range of energies possessed through the valence electrons which is the electrons in the outermost orbit. Such band has the electrons having the highest energy and this can be completely or partially filled. While this band is filled, this means that the electrons involving all permissible energy levels in the band and no electrons can move in a filled band. Therefore an electron in a fully filled band cannot contribute to electric current. This partially filled band can accommodate more electrons.

Energy Gap: The minimum amount of energy which is needed to lift an electron from a valence band to the conduction band is termed as energy gap, and is illustrated by the separation among these two bands, that is valence and conduction bands. Such gap is also termed as forbidden energy gap. This also indicates the bondage of valence electrons to the atom. It means if the energy gap is more, then the valence electrons are strongly bound to the nucleus. That energy gap finds the conductivity of a material.


Related Discussions:- Valence band- conduction band- valence electrons energy gap

Explain about zener diodes, Q. Explain about Zener Diodes? Most diodes ...

Q. Explain about Zener Diodes? Most diodes are not intended to be operated in the reverse breakdown region. Diodes designed expressly to operate in the breakdown region are cal

Digital ttl circuit, Execution of Digital Logic Circuits A safety circ...

Execution of Digital Logic Circuits A safety circuit is employed on a lathe to prevent the motor turning if it is not safe to operate. A series of 2 switches are used to check

Factors which affect the inductance of an inductor, Factors which affect th...

Factors which affect the inductance of an inductor include:  i)  The number of turns of wire (N) - more turns the higher the inductance ii)  The cross-sectional area of the

Button cells, what is a button cells and how is it used on a low current el...

what is a button cells and how is it used on a low current electronic circuit

Vhdl, how to construct universal shift register using D-flipflop and mux??

how to construct universal shift register using D-flipflop and mux??

Physics, what do we mean when we say that an equation is dimensionally corr...

what do we mean when we say that an equation is dimensionally correct?

Connection of shunt capacitors - across individual customers, Connection of...

Connection of Shunt Capacitors - Across Individual Customers The most appropriate manner of improving PF of the distribution system and thereby reducing line losses is to link

Power factor correction, i want to prodused domestic power factor correctio...

i want to prodused domestic power factor correction like industial

Output characteristics , Output Characteristics The output  or drain  ...

Output Characteristics The output  or drain  characteristic of N - Channel  power MOSFET. When gate  is made positive with respect to the source an N type  channel  is formed

Calculate the antenna aperture area, Q. Amicrowave relay systemuses two ide...

Q. Amicrowave relay systemuses two identical horn antennas mounted on towers spaced 40 km apart. If f c = 6 GHz, and each relay hop has L = 60 dB, calculate the antenna aperture a

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd