FIR spectra of C2H2 have been recorded at 0.00096 cm (1) spectral resolution using the Canadian Light Source synchrotron facility. The analysis allowed us to assign 731 new vibration-rotation lines from 48 bands in (C2H2)-C-12, 38 of which are reported for the first time. Two additional bands are assigned to (CH12CH)-C-13. The measured line positions and calculated spectra can be made available to help in the remote sensing of acetylene in the terahertz spectral range. (C) 2010 Elsevier B.V. All rights reserved.