🧪 Carbon Nanotube Chirality Constructor

Every single-wall carbon nanotube is defined by a single pair of integers, its chiral indices (n, m). This simulator builds the real graphene honeycomb lattice for whichever (n, m) you choose, computes the true chiral vector C_h = n·a₁ + m·a₂, and rolls the lattice into a cylinder exactly the way nature does — atom by atom, bond by bond, including the seam where the sheet closes on itself. The tube's diameter and chiral angle come directly from the (n, m) geometry, and its electronic character — metallic or semiconducting — comes from the real (n − m) mod 3 zone-folding rule that governs actual carbon nanotubes. Switch between armchair (n = m), zigzag (m = 0) and chiral (0 < m < n) tubes, toggle between the rolled 3D tube and the flat unrolled sheet, and watch how a two-integer choice determines whether a nanotube conducts like a metal or a semiconductor.