# title
Raman spectra and DFT calculations for tetraterpene hydrocarbons from the L race of the green microalga Botryococcus braunii

# abstract
2016 Elsevier B.V. The green microalga Botryococcus braunii produces large amounts of liquid hydrocarbons that can be used as a renewable source for producing transportation fuels. In the L race of B.braunii the tetraterpene known as lycopadiene accumulates as the main hydrocarbon. Lycopadiene biosynthesis begins with the production of the eight carbon-carbon double bond (C=C) containing molecule lycopaoctaene, which is reduced to lycopadiene through four intermediates containing less C=C bonds. While the biosynthetic pathway for these hydrocarbons has recently been deciphered, a spectroscopic understanding of the molecular structure for these molecules remains to be reported. Here we describe the vibrational frequency assignments for all six L race hydrocarbons using density functional theory (DFT) calculations, showing that these molecules have between 312 and 348 vibrational frequencies. Experimental Raman spectroscopy analysis shows the regions for (C=C) stretch and CH2/CH3 bending vibrations offer unique spectral signatures allowing for the differentiation of several of the hydrocarbons from each other.

# authors[].organizations[].label
Texas A&M Engineering Experiment Station (TEES)

# authors[].organizations[].label
College of Agriculture and Life Sciences

# authors[].organizations[].label
Texas A&M Engineering Experiment Station (TEES)

# authorList[]
Chun, H. J., Waqued, S., Thapa, H. R., Han, A., Yakovlev, V. V., Laane, J., & Devarenne, T. P.