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: ''"Molecular crystal" redirects here. For a solid network of atoms covalently bound together, see Network covalent bonding.'' Molecular solid is a solid composed of molecules held together by the van der Waals forces. Because these dipole forces are weaker than covalent or ionic bonds, molecular solids are soft and have relatively low melting temperature. Pure molecular solids are electrical insulators but they can be made conductive by doping. Examples of molecular solids include hydrocarbons, ice, sugar, fullerenes, sulfur and solid carbon dioxide. ==Structure and composition== The term "molecular solid" may refer not to a certain chemical composition, but to a specific form of a material. For example, solid phosphorus can crystallize in different allotropes called "white", "red" and "black" phosphorus. White phosphorus forms molecular crystals composed of tetrahedral P4 molecules. Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P4 tetrahedra are no longer isolated, but are connected by covalent bonds into polymer-like chains. Heating white phosphorus under high (GPa) pressures converts it to black phosphorus which has a layered, graphite-like structure. The structural transitions in phosphorus are reversible: upon releasing high pressure, black phosphorus gradually converts into the red allotrope, and by vaporizing red phosphorus at 490 °C in inert atmosphere and condensing the vapor, covalent red phosphorus can be transformed back into the white molecular solid. Similarly, yellow arsenic is a molecular solid composed of As4 units; it is metastable and gradually transforms into gray arsenic upon heating or illumination. Some forms of sulfur and selenium are composed of S8 (or Se8) units and are molecular solids at ambient conditions, but they can convert into covalent allotropes having atomic chains extending all through the crystal. Changes in the chemical composition can have even stronger effects on the bonding in solids. For example, whereas both hydrogen and lithium belong to the first group of the periodic table, LiCl is ionic and HCl is a molecular solid. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「: ''"Molecular crystal" redirects here. For a solid network of atoms covalently bound together, see Network covalent bonding.'''''Molecular solid''' is a solid composed of molecules held together by the van der Waals forces. Because these dipole forces are weaker than covalent or ionic bonds, molecular solids are soft and have relatively low melting temperature. Pure molecular solids are electrical insulators but they can be made conductive by doping. Examples of molecular solids include hydrocarbons, ice, sugar, fullerenes, sulfur and solid carbon dioxide.==Structure and composition==*See also higher alkanesThe term "molecular solid" may refer not to a certain chemical composition, but to a specific form of a material. For example, solid phosphorus can crystallize in different allotropes called "white", "red" and "black" phosphorus. White phosphorus forms molecular crystals composed of tetrahedral P4 molecules. Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P4 tetrahedra are no longer isolated, but are connected by covalent bonds into polymer-like chains. Heating white phosphorus under high (GPa) pressures converts it to black phosphorus which has a layered, graphite-like structure.The structural transitions in phosphorus are reversible: upon releasing high pressure, black phosphorus gradually converts into the red allotrope, and by vaporizing red phosphorus at 490 °C in inert atmosphere and condensing the vapor, covalent red phosphorus can be transformed back into the white molecular solid.Similarly, yellow arsenic is a molecular solid composed of As4 units; it is metastable and gradually transforms into gray arsenic upon heating or illumination. Some forms of sulfur and selenium are composed of S8 (or Se8) units and are molecular solids at ambient conditions, but they can convert into covalent allotropes having atomic chains extending all through the crystal.Changes in the chemical composition can have even stronger effects on the bonding in solids. For example, whereas both hydrogen and lithium belong to the first group of the periodic table, LiCl is ionic and HCl is a molecular solid.」の詳細全文を読む : ''"Molecular crystal" redirects here. For a solid network of atoms covalently bound together, see Network covalent bonding.'' Molecular solid is a solid composed of molecules held together by the van der Waals forces. Because these dipole forces are weaker than covalent or ionic bonds, molecular solids are soft and have relatively low melting temperature. Pure molecular solids are electrical insulators but they can be made conductive by doping. Examples of molecular solids include hydrocarbons, ice, sugar, fullerenes, sulfur and solid carbon dioxide. ==Structure and composition== The term "molecular solid" may refer not to a certain chemical composition, but to a specific form of a material. For example, solid phosphorus can crystallize in different allotropes called "white", "red" and "black" phosphorus. White phosphorus forms molecular crystals composed of tetrahedral P4 molecules. Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P4 tetrahedra are no longer isolated, but are connected by covalent bonds into polymer-like chains. Heating white phosphorus under high (GPa) pressures converts it to black phosphorus which has a layered, graphite-like structure. The structural transitions in phosphorus are reversible: upon releasing high pressure, black phosphorus gradually converts into the red allotrope, and by vaporizing red phosphorus at 490 °C in inert atmosphere and condensing the vapor, covalent red phosphorus can be transformed back into the white molecular solid. Similarly, yellow arsenic is a molecular solid composed of As4 units; it is metastable and gradually transforms into gray arsenic upon heating or illumination. Some forms of sulfur and selenium are composed of S8 (or Se8) units and are molecular solids at ambient conditions, but they can convert into covalent allotropes having atomic chains extending all through the crystal. Changes in the chemical composition can have even stronger effects on the bonding in solids. For example, whereas both hydrogen and lithium belong to the first group of the periodic table, LiCl is ionic and HCl is a molecular solid. 抄文引用元・出典: フリー百科事典『 ''Molecular solid is a solid composed of molecules held together by the van der Waals forces. Because these dipole forces are weaker than covalent or ionic bonds, molecular solids are soft and have relatively low melting temperature. Pure molecular solids are electrical insulators but they can be made conductive by doping. Examples of molecular solids include hydrocarbons, ice, sugar, fullerenes, sulfur and solid carbon dioxide.==Structure and composition==*See also higher alkanesThe term "molecular solid" may refer not to a certain chemical composition, but to a specific form of a material. For example, solid phosphorus can crystallize in different allotropes called "white", "red" and "black" phosphorus. White phosphorus forms molecular crystals composed of tetrahedral P4 molecules. Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P4 tetrahedra are no longer isolated, but are connected by covalent bonds into polymer-like chains. Heating white phosphorus under high (GPa) pressures converts it to black phosphorus which has a layered, graphite-like structure.The structural transitions in phosphorus are reversible: upon releasing high pressure, black phosphorus gradually converts into the red allotrope, and by vaporizing red phosphorus at 490 °C in inert atmosphere and condensing the vapor, covalent red phosphorus can be transformed back into the white molecular solid.Similarly, yellow arsenic is a molecular solid composed of As4 units; it is metastable and gradually transforms into gray arsenic upon heating or illumination. Some forms of sulfur and selenium are composed of S8 (or Se8) units and are molecular solids at ambient conditions, but they can convert into covalent allotropes having atomic chains extending all through the crystal.Changes in the chemical composition can have even stronger effects on the bonding in solids. For example, whereas both hydrogen and lithium belong to the first group of the periodic table, LiCl is ionic and HCl is a molecular solid.">ウィキペディア（Wikipedia）』 ■''Molecular solid is a solid composed of molecules held together by the van der Waals forces. Because these dipole forces are weaker than covalent or ionic bonds, molecular solids are soft and have relatively low melting temperature. Pure molecular solids are electrical insulators but they can be made conductive by doping. Examples of molecular solids include hydrocarbons, ice, sugar, fullerenes, sulfur and solid carbon dioxide.==Structure and composition==*See also higher alkanesThe term "molecular solid" may refer not to a certain chemical composition, but to a specific form of a material. For example, solid phosphorus can crystallize in different allotropes called "white", "red" and "black" phosphorus. White phosphorus forms molecular crystals composed of tetrahedral P4 molecules. Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P4 tetrahedra are no longer isolated, but are connected by covalent bonds into polymer-like chains. Heating white phosphorus under high (GPa) pressures converts it to black phosphorus which has a layered, graphite-like structure.The structural transitions in phosphorus are reversible: upon releasing high pressure, black phosphorus gradually converts into the red allotrope, and by vaporizing red phosphorus at 490 °C in inert atmosphere and condensing the vapor, covalent red phosphorus can be transformed back into the white molecular solid.Similarly, yellow arsenic is a molecular solid composed of As4 units; it is metastable and gradually transforms into gray arsenic upon heating or illumination. Some forms of sulfur and selenium are composed of S8 (or Se8) units and are molecular solids at ambient conditions, but they can convert into covalent allotropes having atomic chains extending all through the crystal.Changes in the chemical composition can have even stronger effects on the bonding in solids. For example, whereas both hydrogen and lithium belong to the first group of the periodic table, LiCl is ionic and HCl is a molecular solid.">ウィキペディアで「: ''"Molecular crystal" redirects here. For a solid network of atoms covalently bound together, see Network covalent bonding.''Molecular solid''' is a solid composed of molecules held together by the van der Waals forces. Because these dipole forces are weaker than covalent or ionic bonds, molecular solids are soft and have relatively low melting temperature. Pure molecular solids are electrical insulators but they can be made conductive by doping. Examples of molecular solids include hydrocarbons, ice, sugar, fullerenes, sulfur and solid carbon dioxide.==Structure and composition==*See also higher alkanesThe term "molecular solid" may refer not to a certain chemical composition, but to a specific form of a material. For example, solid phosphorus can crystallize in different allotropes called "white", "red" and "black" phosphorus. White phosphorus forms molecular crystals composed of tetrahedral P4 molecules. Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P4 tetrahedra are no longer isolated, but are connected by covalent bonds into polymer-like chains. Heating white phosphorus under high (GPa) pressures converts it to black phosphorus which has a layered, graphite-like structure.The structural transitions in phosphorus are reversible: upon releasing high pressure, black phosphorus gradually converts into the red allotrope, and by vaporizing red phosphorus at 490 °C in inert atmosphere and condensing the vapor, covalent red phosphorus can be transformed back into the white molecular solid.Similarly, yellow arsenic is a molecular solid composed of As4 units; it is metastable and gradually transforms into gray arsenic upon heating or illumination. Some forms of sulfur and selenium are composed of S8 (or Se8) units and are molecular solids at ambient conditions, but they can convert into covalent allotropes having atomic chains extending all through the crystal.Changes in the chemical composition can have even stronger effects on the bonding in solids. For example, whereas both hydrogen and lithium belong to the first group of the periodic table, LiCl is ionic and HCl is a molecular solid.」の詳細全文を読む ''Molecular solid''' is a solid composed of molecules held together by the van der Waals forces. Because these dipole forces are weaker than covalent or ionic bonds, molecular solids are soft and have relatively low melting temperature. Pure molecular solids are electrical insulators but they can be made conductive by doping. Examples of molecular solids include hydrocarbons, ice, sugar, fullerenes, sulfur and solid carbon dioxide.==Structure and composition==*See also higher alkanesThe term "molecular solid" may refer not to a certain chemical composition, but to a specific form of a material. For example, solid phosphorus can crystallize in different allotropes called "white", "red" and "black" phosphorus. White phosphorus forms molecular crystals composed of tetrahedral P4 molecules. Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P4 tetrahedra are no longer isolated, but are connected by covalent bonds into polymer-like chains. Heating white phosphorus under high (GPa) pressures converts it to black phosphorus which has a layered, graphite-like structure.The structural transitions in phosphorus are reversible: upon releasing high pressure, black phosphorus gradually converts into the red allotrope, and by vaporizing red phosphorus at 490 °C in inert atmosphere and condensing the vapor, covalent red phosphorus can be transformed back into the white molecular solid.Similarly, yellow arsenic is a molecular solid composed of As4 units; it is metastable and gradually transforms into gray arsenic upon heating or illumination. Some forms of sulfur and selenium are composed of S8 (or Se8) units and are molecular solids at ambient conditions, but they can convert into covalent allotropes having atomic chains extending all through the crystal.Changes in the chemical composition can have even stronger effects on the bonding in solids. For example, whereas both hydrogen and lithium belong to the first group of the periodic table, LiCl is ionic and HCl is a molecular solid.」の詳細全文を読む スポンサード リンク
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