Bravais lattice is a set of points constructed by translating a single point in discrete steps by a set of basis vectors. The French crystallographer Auguste Bravais (1811-1863) established that in three-dimensional space only fourteen different lattices may be constructed. All crystalline materials recognised till now fit in one of these arrangements. The fourteen three-dimensional lattices, classified by crystal system, are shown to the bottom.
Crystal system
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Bravais lattices
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cubic a=b=c α=β=γ=90° |
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simple cubic
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body-centered cubic
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face-centered cubic
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tetragonal a=b≠c α=β=γ=90° |
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simple tetragonal
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body-centered tetragonal
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orthorhombic a≠b≠c α=β=γ=90° |
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simple orthorhombic
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base-centered orthorhombic
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body-centered orthorhombic
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face-centered orthorhombic
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monoclinic a≠b≠c α=γ=90°≠β |
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simple monoclinic
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base-centered monoclinic
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hexagonal a=b≠c α=β=90° γ=120° |
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hexagonal
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rhombohedral a=b=c α=β=γ≠90° |
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rhombohedral
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triclinic a≠b≠c α≠β≠γ≠90° |
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triclinic
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Calcination is a process of driving out crystal water from crystal salts by heating.
Anhydrous (without water) is an applied to minerals which do not contain water of crystallization or water of chemical combination. For example, strongly heated copper (II) sulphate pent hydrate (CuSO4•5H2O) produces anhydrous copper (II) sulphate (CuSO4). Less stable and more dangerous to use than hydrated.
Antimony has been known since ancient times. The origin of the name comes from the Latin word stibium meaning mineral stibnite. It is hard, brittle, silvery-white semimetal. Stable in dry air. Toxic by ingestion or inhalation. Antimony is found in stibnite (Sb2S3) and in valentinite (Sb2O3). It is alloyed with other metals to increase their hardness. Also in the manufacture of a few special types of semiconductor devices. Also in plastics and chemicals. A few kinds of over-the-counter cold and flu remedies use antimony compounds.
Base-centered or side-centered or end-centered monoclinic lattice (monoclinic-C), like all lattices, has lattice points at the eight corners of the unit cell plus additional points at the centers of two parallel sides of the unit cell. It has unit cell vectors a≠b≠c, and interaxial angles α=γ=90°≠β.
Base-centered or side-centered or end-centered monoclinic lattice (orthorhombic-C), like all lattices, has lattice points at the eight corners of the unit cell plus additional points at the centers of two parallel sides of the unit cell. It has unit cell vectors a≠b≠c and interaxial angles α=β=γ=90°.
Equation of state is an equation relating the pressure, volume, and temperature of a substance or system. Equation of state for ideal gas
where p is pressure, V molar volume, T temperature, and R the molar gas constant (8.314 JK-1mol-1).
Blackbody radiation is the radiation emitted by a perfect blackbody, i.e., a body which absorbs all radiation incident on it and reflects none. The primary law governing blackbody radiation is the Planck Radiation Law, which governs the intensity of radiation emitted by unit surface area into a fixed direction (solid angle) from the blackbody as a function of wavelength for a fixed temperature. The Planck Law can be expressed through the following equation
where λ is the wavelength, h is Planck’s constant, c is the speed of light, k is the Boltzmann constant, and T is the temperature.
Body-centered cubic lattice (bcc or cubic-I), like all lattices, has lattice points at the eight corners of the unit cell plus an additional points at the center of the cell. It has unit cell vectors a = b = c and interaxial angles α=β=γ=90°.
The simplest crystal structures are those in which there is only a single atom at each lattice point. In the bcc structures the spheres fill 68 % of the volume. The number of atoms in a unit cell is two (8 × 1/8 + 1 = 2). There are 23 metals that have the bcc lattice.
Glauber’s salt is sodium sulphate decahydrate (Na2SO4·10H2O). Loses water of hydration at 100 °C. Energy storage capacity is more than seven times that of water.
Generalic, Eni. "Idealni kristal." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
Glossary
Periodic Table