NCCNCCN mol3089 0_1 NCC[NH2+]CCN mol3089 1_1 NCCNCC[NH3+] mol3089 1_2 NCC[NH2+]CC[NH3+] mol3089 2_1 [NH3+]CCNCC[NH3+] mol3089 2_2 [NH3+]CC[NH2+]CC[NH3+] mol3089 3_1