Table 3. Comparison of selected (X-ray and DFT) geometric data (Å, °).

Bonds/angles	X-ray	B3LYP/6–311G(d,p)
O1—C7	1.225 (2)	1.25497
N1—C7	1.384 (2)	1.40076
N1—C6	1.397 (2)	1.40603
N1—C8	1.452 (2)	1.46502
N2—C7	1.379 (2)	1.39180
N2—C1	1.395 (2)	1.40574
N2—C18	1.450 (2)	1.47028
N3—N4	1.314 (2)	1.32954
N3—C10	1.358 (3)	1.37406
N4—N5	1.347 (2)	1.38781
N5—C9	1.356 (2)	1.37548
N5—C11	1.452 (2)	1.47090
C7—N1—C6	109.72 (15)	109.64541
C7—N1—C8	123.68 (15)	122.59694
C6—N1—C8	125.96 (15)	127.83740
C7—N2—C1	109.90 (15)	109.86320
C7—N2—C18	123.91 (16)	122.77835
C1—N2—C18	125.82 (16)	128.23580
N4—N3—C10	108.55 (17)	108.75382
N3—N4—N5	107.17 (16)	107.07997
N4—N5—C9	111.14 (15)	110.25168
N4—N5—C11	118.44 (16)	118.90455