Diamondoids were first discovered and isolated from Czechoslovakian petroleum in 1933. Adamantane, from the Greek for diamond, was the first isolated substance. This name was chosen because adamantane has the same internal carbon framework as the diamond crystal lattice, highly symmetrical and strain free.

Adamantane, the smallest diamondoid, is a cell consisting of 10 carbon atoms.  The next higher diamondoids, diamantane and triamantane, consist of two and three unit cells respectively. Adamantane, diamantane, and triamantane are sometimes referred to as lower diamondoids. Each of the first three members of the series exists as a single isomer.  Higher diamondoids begin with tetramantane, which consists of four crystal cages of the diamond lattice.  These higher members in the diamondoid series can exist in more than one isomeric form.

The lower diamondoids, previously found in petroleum, have been chemically synthesized.  However efforts by others to synthesize higher diamondoids have failed, other than one tetramantane made with great difficulty and low yield.

Nanotechnology researchers have for years imagined what they might be able to make with higher diamondoids, but until now they have been able to explore those ideas only with molecular simulations studies. Chevron research were the first to identify, isolate and produce higher diamondoids up to undecamantane (11 diamond crystal cages), which corresponds to a diamond of less than a billionth of a billionth of a carat.  All of the higher diamondoids come in several different shapes, including straight rods and left- and right-handed helices.

Our discovery originated out of pure scientific curiosity. While characterizing materials residue that plugged refinery equipment, we saw lower diamondoids. We speculated that the sample could also contain higher diamondoids, but the non-diamondoids materials had to be removed first in order to see the higher diamondoids. Chevron research used its core scientific, technical and operations capabilities to identify, isolate, and produce dozens of higher diamondoids in high purity from petroleum sources. Higher diamondoids occur naturally in certain hydrocarbon sources.

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