Polyhedral symbol has 25 symbols one of which is Trigonal Planar.
HBPY-9 TPRS-9 TPRS-8 TPRT-8 OCT-8 HBPY-8 DD-8 SAPR-8 TPRS-7 CU-8 OCF-7 TPR-6 PBPY-7 OC-6 SPY-5 TBPY-5 SS-4 SPY-4 SP-4 T-4 TS-3 TPY-3 TP-3 A-2 L-2 trigonal planar  3 coordinate 
