Fig. 2: The orientational structure of NMP and DMAc around SWCNTs and intersolvent structure.

a,b, cRDFs of constituent solvent atoms from the SWCNT surface, overlaid with schematic orientations of solvents versus nanotube surface for a monolayer of solvent molecules closest to the SWCNT, as seen in partial g(r) as small peaks at equivalent distances (a), and for solvents at further distances with dipole-ordered orientation with oxygen the furthest atom from the SWCNT, and CH_n species closest to the SWCNT surface (b). Species in b stack with the molecular plane perpendicular to the solvent–SWCNT vector as seen in the distribution of orientational histograms (Extended Data Fig. 5). Atom/line colours: O, orange; N, blue; carbonyl C, black; H, white. NMP: N-methyl C, pink; C3, grey; C4, green; C5, blue-green. DMAc: acetic C, grey; E-methyl C, green; Z-methyl C, pink. c, Distribution of orientations of the angle between the amide dipole vector and a (radial) vector pointing away from the nanotube central axis, normalized with 1 as an even distribution across all angles. Distances from the SWCNT surface are binned by solvation shells and at 5 Å intervals at further distances. d, Amide–amide SDF for solvent molecules in the first SWCNT solvation shell, the second SWNCT solvation shell, and beyond the second SWCNT solvation shell (>12.2 Å and >11.9 Å from the SWNCT wall for NMP and DMAc, respectively), for NMP and DMAc. The amide–amide SDF of all solvents is provided in Extended Data Fig. 6.