Which material from the following has the highest transparency?

magnetic permeability, relative increase or decrease in the resultant B established within the material by a magnetizing field divided by the H of the magnetizing field. Magnetic μ (Greek mu) is thus defined as μ = B/ H. Magnetic B is a measure of the actual magnetic field within a material considered as a concentration of magnetic field lines, or flux, per unit cross-sectional area. Magnetic field strength H is a measure of the magnetizing field produced by In empty, or free, space the magnetic flux density is the same as the magnetizing field because there is no matter to modify the field. In centimetre–gram–second (cgs) units, the permeability B/ H of space is dimensionless and has a value of 1. In metre–kilogram–second (mks) and B and H have different μ 0) was defined as equal to 4 π × 10 - 7 μ 0 is no longer equal to 4 π × 10 - 7 weber per ampere-metre and must be determined experimentally. (However, [ μ 0/4 π × 10 - 7] is 1.00000000055, still very close to its former value.) In these systems the permeability, B/ H, is called the absolute permeability μ of the medium. The relative permeability μ r is then defined as the ratio μ/ μ 0, which is dimensionless. Thus, the relative permeability of free space, or

https://chem.libretexts.org/@app/auth/3/login?returnto=https%3A%2F%2Fchem.libretexts.org%2FBookshelves%2FInorganic_Chemistry%2FBook%253A_Introduction_to_Inorganic_Chemistry_(Wikibook)%2F10%253A_Electronic_Properties_of_Materials_-_Superconductors_and_Semiconductors%2F10.05%253A_Semiconductors-_Band_Gaps_Colors_Conductivity_and_Doping Expand/collapse global hierarchy • Home • Bookshelves • Inorganic Chemistry • Book: Introduction to Inorganic Chemistry (Wikibook) • 10: Electronic Properties of Materials - Superconductors and Semiconductors • 10.5: Semiconductors- Band Gaps, Colors, Conductivity and Doping Expand/collapse global location \( \newcommand\) • • • Semiconductors, as we noted above, are somewhat arbitrarily defined as insulators with band gap energy Si > Ge >α-Sn E gap (eV): 5.4 1.1 0.7 0.0 This trend can be understood by recalling that E gap is related to the energy splitting between bonding and antibonding orbitals. This difference decreases (and bonds become weaker) as the principal quantum number increases. (2) For isoelectronic compounds, increasing ionicity results in a larger band gap. Ge < GaAs < ZnSe 0.7 1.4 2.8 eV Sn < InSb < CdTe < AgI 0.0 0.2 1.6 2.8 eV This trend can also be understood from a simple MO picture, as we discussed in Ch. 2. As the electronegativity difference Δχ increases, so does the energy difference between bonding and antibonding orbitals. The band gap is a very important property of a semiconductor because it determines its color a...

Introduction to Infrared (IR) Infrared (IR) radiation is characterized by wavelengths ranging from 0.750 -1000μm (750 - 1000000nm). Due to limitations on detector range, IR radiation is often divided into three smaller regions: 0.750 - 3μm, 3 - 30μm, and 30 - 1000μm – defined as near-infrared (NIR), mid-wave infrared (MWIR), and far-infrared (FIR), respectively (Figure 1). Figure 1: Electromagnetic Spectrum The Importance of Using the Correct Material Since infrared light is comprised of longer wavelengths than visible light, the two regions behave differently when propagating through the same optical medium. Some materials can be used for either IR or visible applications, most notably Transmission The foremost attribute defining any material is transmission. Transmission is a measure of throughput and is given as a percentage of the incident light. IR materials are usually opaque in the visible while visible materials are usually opaque in the IR; in other words, they exhibit nearly 0% transmission in those wavelength regions. For example, consider Figure 2: Uncoated Silicon Transmission Curve Index of Refraction While it is mainly transmission that classifies a material as either an IR or visible material, another important attribute is index of refraction $ \small $increases (Figure 3). Figure 3: Light Refraction from a Low Index to a High Index Medium The index of refraction ranges from approximately 1.45 - 2 for visible materials and 1.38 - 4 for IR materials. In man...

We have Visible Light Absorption Atoms and molecules contain electrons. It is often useful to think of these electrons as being attached to the atoms by springs. The electrons and their attached springs have a tendency to vibrate at specific frequencies. Similar to a tuning fork or even a musical instrument, the electrons of atoms have a Visible Light Reflection and Transmission Reflection and transmission of light waves occur because the frequencies of the light waves do not match the natural frequencies of vibration of the objects. When light waves of these frequencies strike an object, the electrons in the atoms of the object begin vibrating. But instead of vibrating in resonance at a large amplitude, the electrons vibrate for brief periods of time with small amplitudes of vibration; then the energy is reemitted as a light wave. If the object is transparent, then the vibrations of the electrons are passed on to neighboring atoms through the bulk of the material and reemitted on the opposite side of the object. Such frequencies of light waves are said to be transmitted. If the object is opaque, then the vibrations of the electrons are not passed from atom to atom through the bulk of the material. Rather the electrons of atoms on the material's surface vibrate for short periods of time and then reemit the energy as a reflected light wave. Such frequencies of light are said to be reflected. Where Does Color Come From? The color of the objects that we see is largely due to ...

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