“…Likewise, we had studied the m 12 bands of 12 C 2 D 4 [14], of cis-12 C 2 H 2 D 2 [18], of trans-12 C 2 H 2 D 2 [19], of 13 C 2 H 4 [22] and of 12 C 2 H 3 D [25] at high-resolution to improve on or to derive new ground and m 12 = 1 rovibrational constants. The present work is aimed at the analysis of the m 12 band of 13 C 12 CH 4 which was measured with a resolution of 0.0063 cm À1 .…”