The six molecular 1-x-y-1 building blocks form the basis for constructing more complicated branched alkanes, similar to the approach taken in Ref. 6 for linear alkanes. The conformational potential energy landscape of any branched alkane is a sum of building block functions g 1-x-y-1 : S 1 → R. The sublevelset persistence barcodes of the six g 1-x-y-1 (Figure ) are computed using the GUDHI software package and our code , which is based on the code at Ref. 34. We discretize