Quadruple bond Quadruple bond A quadruple bond is a type of chemical bond between two atoms involving eight electrons. This bond is an extension of the more familiar types double bonds and triple bonds. Stable quadruple bonds are most common among the transition metals in the middle of the d-block, such as rhenium, tungsten, molybdenum and chromium. Typically the ligands that support quadruple bonds are π-donors, not π-acceptors. Chromium(II) acetate, Cr("μ"-OCCH)(HO), was the first chemical compound containing a quadruple bond to be synthesized. It was described in 1844 by E. Peligot, although its distinctive bonding was not recognized for more than a
Double (basketball) seasons. A quadruple-double is the accumulation of a double-digit number total in four of the five categories in a game. This has occurred four times in the NBA. A quintuple-double is the accumulation of a double-digit number total in all five categories in a game. Two quintuple-doubles have been recorded at the high school level, by Tamika Catchings and Aimee Oertner, but none have occurred in a college or professional game. A similar accomplishment is the five-by-five, which is the accumulation of at least five points, five rebounds, five assists, five steals, and five blocks in a game. In the