For 10 points, name this element found naturally in borax and kernite, a metalloid with atomic number five and symbol B.
This element's geometrically frustrated beta rhombohedral phase is equivalent to an antiferromagnetic Ising model on an expanded kagome lattice. The Kucherov reaction hydrates hydrocarbons using this element's triflouride as a catalyst, while (*) Wade's Rules govern the bonding of this element to Hydrogen. This element's carbide's ability to absorb neutrons without forming radionuclides allows for its use in shielding and shutdown pellets in nuclear plants. Organic acids of this element can be bonded to halides with the help of a Palladium catalyst in Suzuki Coupling.  Compounds of this element commonly violate the octet rule. For 10 points, name this element found naturally in borax and kernite, a metalloid with atomic number five and symbol B.
This element's geometrically frustrated beta rhombohedral phase is equivalent to an antiferromagnetic Ising model on an expanded kagome lattice.
{Boron}