The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). Together with hydrogen they constitute group 1, which lies in the s-block of the periodic table. All alkali metals have their outermost electron in an s-orbital: this shared electron configuration results in their having very similar characteristic properties. Indeed, the alkali metals provide the best example of group trends in properties in the periodic table, with elements exhibiting well-characterised homologous behaviour. This family of elements is also known as the lithium family after its leading element.
Phosphorus pentachloride is the chemical compound with the formula PCl5. It is one of the most important phosphorus chlorides/oxychlorides, others being PCl3 and POCl3. PCl5 finds use as a chlorinating reagent. It is a colourless, water-sensitive solid, although commercial samples can be yellowish and contaminated with hydrogen chloride.
In chemistry, a phosphide is a compound containing the P3− ion or its equivalent. Many different phosphides are known, with widely differing structures. Most commonly encountered on the binary phosphides, i.e. those materials consisting only of phosphorus and a less electronegative element. Numerous are polyphosphides, which are solids consisting of anionic chains or clusters of phosphorus. Phosphides are known with the majority of less electronegative elements with the exception of Hg, Pb, Sb, Bi, Te, and Po. Finally, some phosphides are molecular.
Ozonide is the polyatomic anion O−3. Cyclic organic compounds formed by the addition of ozone to an alkene are also called ozonides.
Sodium phosphide is the inorganic compound with the formula Na3P. It is a black solid. It is often described as Na+ salt of the P3− anion. Na3P is a source of the highly reactive phosphide anion. It should not be confused with sodium phosphate, Na3PO4.
Elemental phosphorus can exist in several allotropes, the most common of which are white and red solids. Solid violet and black allotropes are also known. Gaseous phosphorus exists as diphosphorus and atomic phosphorus.
The phosphidosilicates or phosphosilicides are inorganic compounds containing silicon bonded to phosphorus and one or more other kinds of elements. In the phosphosilicates each silicon atom is surrounded by four phosphorus atoms in a tetrahedron. The triphosphosilicates have a SiP3 unit, that can be a planar triangle like carbonate CO3. The phosphorus atoms can be shared to form different patterns e.g. [Si2P6]10− which forms pairs, and [Si3P7]3− which contains two-dimensional double layer sheets. [SiP4]8− with isolated tetrahedra, and [SiP2]2− with a three dimensional network with shared tetrahedron corners. SiP clusters can be joined, not only by sharing a P atom, but also by way of a P-P bond. This does not happen with nitridosilicates or plain silicates.
The phosphaethynolate anion, also referred to as PCO, is the phosphorus-containing analogue of the cyanate anion with the chemical formula [PCO]− or [OCP]−. The anion has a linear geometry and is commonly isolated as a salt. When used as a ligand, the phosphaethynolate anion is ambidentate in nature meaning it forms complexes by coordinating via either the phosphorus or oxygen atoms. This versatile character of the anion has allowed it to be incorporated into many transition metal and actinide complexes but now the focus of the research around phosphaethynolate has turned to utilising the anion as a synthetic building block to organophosphanes.
A chloride nitride is a mixed anion compound containing both chloride (Cl−) and nitride ions (N3−). Another name is metallochloronitrides. They are a subclass of halide nitrides or pnictide halides.
A Phosphide chloride is a mixed anion compound containing both phosphide (P3−) and chloride (Cl−) ions.
Phosphide silicides or silicide phosphides or silicophosphides are compounds containing anions composed of silicide (Si4−) and phosphide (P3−). They can be considered as mixed anion compounds. They are distinct from the phosphidosilicates, which have the phosphorus bonded to the silicon. Related compounds include the phosphide carbides, germanide phosphides, nitride silicides, and antimonide silicides.
Phosphanides are chemicals containing the [PH2]− anion. This is also known as the phosphino anion or phosphido ligand. The IUPAC name can also be dihydridophosphate(1−).
Lutetium phosphide is an inorganic compound of lutetium and phosphorus with the chemical formula LuP. The compound forms dark crystals, does not dissolve in water.
Praseodymium monophosphide is an inorganic compound of praseodymium and phosphorus with the chemical formula PrP. The compound forms crystals.
Lanthanum phosphide is an inorganic compound of lanthanum and phosphorus with the chemical formula LaP.
Lithium arsenide describes inorganic compounds with the chemical formula LixAs where x can range from about 0.5 to 3. A common derivative is Li3As, which is prepared by the reduction of arsenic with a solution of lithium in ammonia. It can also be produced by heating the elements.
Phosphide iodides or iodide phosphides are compounds containing anions composed of iodide (I−) and phosphide (P3−). They can be considered as mixed anion compounds. They are in the category of pnictidehalides. Related compounds include the phosphide chlorides, arsenide iodides antimonide iodides and phosphide bromides.
Terbium compounds are compounds formed by the lanthanide metal terbium (Tb). Terbium generally exhibits the +3 oxidation state in these compounds, such as in TbCl3, Tb(NO3)3 and Tb(CH3COO)3. Compounds with terbium in the +4 oxidation state are also known, such as TbO2 and BaTbF6. Terbium can also form compounds in the 0, +1 and +2 oxidation states.
Phosphidogermanates are chemical compounds that have phosphorus bound to germanium to yield anions. They are in the category of phosphidotetrelates and also pnictides. They are analogous to nitridogermanates, phosphidoaluminates, phosphidogallates, phosphidoindates, phosphidosilicates or phosphidostannates.
Zirconium monophosphide is a binary inorganic compound of zirconium metal and phosphorus with the chemical formula ZrP.
