Ideal crystal is a single crystal with a perfectly regular lattice that contains no impurities, imperfections, or other defects.
Anisotropic crystal is a crystal that exhibits different properties when tested along axes in different directions.
Crystal is a solid with a regular geometric shape, having a characteristic internal structure and enclosed by symmetrically arranged plane surfaces, intersecting at definite and characteristic angles. In crystals the particles (atoms, ions, or molecules) have a regular three-dimensional repeating arrangement in space. This is called the crystal structure. The crystal lattice is the arrangement of points in space at which the particles are positioned.
Ideal gas is a gas in which there is complete absence of cohesive forces between the component molecules; the behaviour of such a gas can be predicted accurately by the ideal gas equation through all ranges of temperature and pressure. The concept is theoretical, since no actual gas meets the ideal requirement.
The measured properties of an isotropic crystal are independent of the axis of testing. Opposite of anisotropic.
Liquid crystals or crystalline liquids are a physical state between crystals and melts. The liquid crystalline phase - the so-called mesophase - is formed at the melting point. The most important (usable) mesophases are nematic, cholesteric and smectic phase, having different molecular orientations.
Perfect crystal is a crystal with no defects or impurities made of completely identical repeating subunits. Further, a perfect crystal has only one possible arrangement of subunits, with every subunit making exactly the same contribution to the total energy of the crystal.
Crystal water is water contained in certain salt crystals. It can be removed by heating. Crystals that contain crystal water are called hydrated and their salts hydrates.
Crystallisation is process in which the melted substance from a saturated solution turns into solid substance (crystal).
Generalic, Eni. "Idealni kristal." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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