A Study of the Far Infrared Spectrum of N-Acetyl-D-Glucosamine Using THz-TDS, FTIR, and Semiempirical Quantum Chemistry Methods

Table 1

Comparison of the experimental bond lengths (in Å) with those of the geometry optimized with the PM6 method. The unsigned mean error (UME) is 1.30%.

Bond	Experimental distance	PM6-calculated distance	Error
C1-C2	1.5281	1.5499	1.43%
C2-C3	1.5367	1.5477	0.72%
C3-C4	1.5344	1.5464	0.78%
C4-C5	1.5504	1.5392	0.72%
C5-C6	1.5201	1.5298	0.64%
C7-C8	1.5126	1.4903	1.47%
C2-N1	1.4763	1.4745	0.12%
C7-N1	1.3800	1.3819	0.14%
C1-O1	1.3935	1.4167	1.66%
C3-O2	1.4511	1.4319	1.32%
C4-O3	1.4685	1.4382	2.06%
C1-O4	1.4593	1.4248	2.36%
C5-O4	1.4598	1.4581	0.12%
C6-O5	1.3908	1.4402	3.55%
C7-O6	1.2177	1.2465	2.37%