Polarization and Polarizability - Revision history

Cmditradmin: /* Mechanisms for polarization */

2010-01-05T22:31:45Z

Mechanisms for polarization

← Older revision		Revision as of 15:31, 5 January 2010
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	[[Image:PI_orbit_anim.gif]]		[[Image:PI_orbit_anim.gif]]

			The speed of polarization determines the speed of modulation which is needed for telecommunications or computing. Electronic polarization removes the current speed barrier due to the use of lithium niobate in fiberoptic modulators.

	[[Image:organic_modulation_speed.png\|thumb\|400px\|The advantage of organic molecules is high frequency modulation.]]		[[Image:organic_modulation_speed.png\|thumb\|400px\|The advantage of organic molecules is high frequency modulation.]]

2010-01-05T22:28:56Z

Mechanisms for polarization

← Older revision		Revision as of 15:28, 5 January 2010
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	[[Image:organic_modulation_speed.png\|thumb\|400px\|The advantage of organic molecules is high frequency modulation.]]		[[Image:organic_modulation_speed.png\|thumb\|400px\|The advantage of organic molecules is high frequency modulation.]]
			<br clear='all'>

	=== Linear polarizability ===		=== Linear polarizability ===

2010-01-05T22:28:37Z

Mechanisms for polarization

← Older revision		Revision as of 15:28, 5 January 2010
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	[[Image:PI_orbit_anim.gif]]		[[Image:PI_orbit_anim.gif]]

			[[Image:organic_modulation_speed.png\|thumb\|400px\|The advantage of organic molecules is high frequency modulation.]]

	=== Linear polarizability ===		=== Linear polarizability ===

2009-12-29T19:27:57Z

← Older revision		Revision as of 12:27, 29 December 2009
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	[[category:polarization]]		[[category:polarization]]
			[[category:molecular orbitals]]
	<br clear='all'>		<br clear='all'>
	<table id="toc" style="width: 100%">		<table id="toc" style="width: 100%">

2009-12-28T21:19:59Z

Dielectric Constant

← Older revision		Revision as of 14:19, 28 December 2009
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	:<math>\omega\,\!</math> is the frequency		:<math>\omega\,\!</math> is the frequency

	:<math>\chi_{ij}(\omega)\,\!</math> is the linear susceptibility of an ensemble of molecules.		:<math>\chi_{ij}(\omega)\,\!</math> is the linear susceptibility tensor of an ensemble of molecules.

	Note that the vectorial and tensor aspects of E and <math>\chi\,\!</math> have been ignored to simplify notation.		Note that the vectorial and tensor aspects of E and <math>\chi\,\!</math> have been ignored to simplify notation.

2009-12-28T21:18:38Z

Linear polarizability

← Older revision		Revision as of 14:18, 28 December 2009
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	:<math>\mu\,\!</math> is the dipole moment		:<math>\mu\,\!</math> is the dipole moment

	:<math>\alpha\,\!</math> is the linear polarizability, (slope of the line)		:<math>\alpha\,\!</math> is the linear polarizability, (slope of the line)(a second-rank tensor)

	:<math>\Epsilon\,\!</math> is electric field		:<math>\Epsilon\,\!</math> is electric field

2009-12-22T00:13:58Z

← Older revision		Revision as of 17:13, 21 December 2009
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	During the process there is no net transfer of energy to the material. However if the frequency of light approaches the natural resonance of the molecule it is possible to transfer to energy to the molecule giving it an excited state, or producing heat or other chemicial reactions.		During the process there is no net transfer of energy to the material. However if the frequency of light approaches the natural resonance of the molecule it is possible to transfer to energy to the molecule giving it an excited state, or producing heat or other chemicial reactions.

			[[category:polarization]]

	<br clear='all'>		<br clear='all'>
	<table id="toc" style="width: 100%">		<table id="toc" style="width: 100%">

2009-12-22T00:04:48Z

Mechanisms for polarization

← Older revision		Revision as of 17:04, 21 December 2009
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	Here is an hydrogen atom in an oscillating electric field. The atom is is oscillating as the electrons are being displaced and the energy levels are changing.		Here is an hydrogen atom in an oscillating electric field. The atom is is oscillating as the electrons are being displaced and the energy levels are changing.

	[[Image:Hydrogen_polar.~~gifs~~]]		[[Image:Hydrogen_polar.gif]]

	In an atom with π orbitals there is more polarizability in the π orbitals than in the σ orbitals. Dyes are typically π conjugated compounds because π orbitals are more polarizable in the visible spectrum.		In an atom with π orbitals there is more polarizability in the π orbitals than in the σ orbitals. Dyes are typically π conjugated compounds because π orbitals are more polarizable in the visible spectrum.

2009-12-22T00:04:10Z

Mechanisms for polarization

← Older revision		Revision as of 17:04, 21 December 2009
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	Here is an hydrogen atom in an oscillating electric field. The atom is is oscillating as the electrons are being displaced and the energy levels are changing.		Here is an hydrogen atom in an oscillating electric field. The atom is is oscillating as the electrons are being displaced and the energy levels are changing.

	[[Image:Hydrogen_polar.~~gif~~]]		[[Image:Hydrogen_polar.gifs]]

	In an atom with π orbitals there is more polarizability in the π orbitals than in the σ orbitals. Dyes are typically π conjugated compounds because π orbitals are more polarizable in the visible spectrum.		In an atom with π orbitals there is more polarizability in the π orbitals than in the σ orbitals. Dyes are typically π conjugated compounds because π orbitals are more polarizable in the visible spectrum.

2009-12-14T23:02:14Z

Mechanisms for polarization

← Older revision		Revision as of 16:02, 14 December 2009
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	If there is an oscillating electronic field it needs to be matched to the timescale of the polarization mechanism. Only those components that react as fast or faster than the frequency will make a contribution to the bulk polarization of the material. The following animation demonstrates these four types. Click the switches to apply an electric field.		If there is an oscillating electronic field it needs to be matched to the timescale of the polarization mechanism. Only those components that react as fast or faster than the frequency will make a contribution to the bulk polarization of the material. The following animation demonstrates these four types. Click the switches to apply an electric field.

			<div id="Flash">Four kinds of polarization animation</div>

	<swf width="600" height="500">http://depts.washington.edu/cmditr/media/01 Polarization Mechanisms.swf</swf>		<swf width="600" height="500">http://depts.washington.edu/cmditr/media/01 Polarization Mechanisms.swf</swf>