#atomic number bond distances for single, double and triple bond (-1 no bond)
1	0.74	-1	-1
2	0.77429209	-1	-1
5	1.23	1.19	1.18
6	1.09	1.076	1.06
7	1.04	1.02	1.01
8	0.96	0.957	-1
14	1.48	1.48	1.48
15	1.42	-1	-1
16	1.35	-1	-1
17	1.29	-1	-1
20	1.09	1.09	-1
34	1.47	-1	-1
35	1.44	-1	-1