Tuning Lewis Acidity by a Transannular p? -?* Interaction between Boron and Silicon/Germanium Atoms Supported by a Cage-Shaped Framework.

See more Germanium products. Germanium (atomic symbol: Ge, atomic number: 32) is a Block P, Group 14, Period 4 element with an atomic weight of 72.63. The number of electrons in each of germanium's shells is 2, 8, 18, 4 and its electron configuration is [Ar] 3d¹⁰ 4s² 4p². The germanium atom has a radius of 122.5 pm and a Van der Waals radius of 211 pm. Germanium was first discovered by Clemens Winkler in 1886. In its elemental form, germanium is a brittle grayish white semi-metallic element. Germanium is too reactive to be found naturally on Earth in its native state. It is commercially obtained from zinc ores and certain coals. It is also found in argyrodite and germanite. It is used extensively as a semiconductor in transitors, solar cells, and optical materials. Other applications include acting an alloying agent, as a phosphor in fluorescent lamps, and as a catalyst. The name Germanium originates from the Latin word "Germania" meaning "Germany."

See more Boron products. Boron (atomic symbol: B, atomic number: 5) is a Block P, Group 13, Period 2 element with an atomic weight of 10.81. The number of electrons in each of boron's shells is 2, 3 and its electron configuration is [He] 2s² 2p¹. The boron atom has a radius of 90 pm and a Van der Waals radius of 192 pm. Boron was discovered by Joseph Louis Gay-Lussac and Louis Jacques Thénard in 1808 and was first isolated by Humphry Davy later that year. Boron is classified as a metalloid is not found naturally on earth. Along with carbon and nitrogen, boron is one of the few elements in the periodic table known to form stable compounds featuring triple bonds. Boron has an energy band gap of 1.50 to 1.56 eV, which is higher than that of either silicon or germanium. The name Boron originates from a combination of carbon and the Arabic word buraqu meaning borax.

See more Silicon products. Silicon (atomic symbol: Si, atomic number: 14) is a Block P, Group 14, Period 3 element with an atomic weight of 28.085. The number of electrons in each of Silicon's shells is 2, 8, 4 and its electron configuration is [Ne] 3s² 3p². The silicon atom has a radius of 111 pm and a Van der Waals radius of 210 pm. Silicon was discovered and first isolated by Jöns Jacob Berzelius in 1823. Silicon makes up 25.7% of the earth's crust, by weight, and is the second most abundant element, exceeded only by oxygen. The metalloid is rarely found in pure crystal form and is usually produced from the iron-silicon alloy ferrosilicon. Silica (or silicon dioxide), as sand, is a principal ingredient of glass, one of the most inexpensive of materials with excellent mechanical, optical, thermal, and electrical properties. Ultra high purity silicon can be doped with boron, gallium, phosphorus, or arsenic to produce silicon for use in transistors, solar cells, rectifiers, and other solid-state devices which are used extensively in the electronics industry.The name Silicon originates from the Latin word silex which means flint or hard stone.