Nanographenes are prospective candidates for spintronic materials that feature spin-polarization at zigzag edges. Triangulenes possess a distinct rule of large total spins analogous to transition metal elements and may be regarded as artificial atoms. In this work, we explore design principles using triangulene building blocks to construct nanographene fragments with various shapes and sizes including simple dimeric systems, rhombenes, double-arrow systems, and superzethrenes. Empirical rules for each system relating their sizes and the most stable high spin states are derived, which correspond to the ferromagnetic arrangement of their constituent triangulene units. Coupling mechanisms constituting effective triangulene units are proposed for each system rationalized by Clar sextet Lewis structures. We find that both the spin multiplicities and exchange energies within 100–l02 meV can be modulated by the connection scheme and the bridge geometry. Our results provide numerical references and valuable empirical rules of molecular design models for future all-carbon-based spintronics.

Power shortage is one of critical issues stalling the development of wireless sensor networks. This paper attempts to address this issue by means of microwave power transmission. In this paper, we propose a sensor node framework using a high-frequency microwave power transmitting module to allow sensor nodes to transmit power to others. We introduce the process of exchanging power between two adjacent sensor nodes and design a power transmission routing protocol called PTR in this paper. PTR optimizes the power transmission of a whole network so that the power of energy sources can efficiently reach any sensor node in the network. We have done simulations and analysis on this framework and the results are positive.