Electrically driven singlet-triplet transition in triangulene spin-1 chains

Recently, graphene triangulene chains have been synthesized and their magnetic response has analyzed by STM methods Mishra coworkers (Nature 598, 287 (2021)). Motivated this study, we determine the exchange bilinear biquadratic constants of calculating two-spin rotations in spirit force theorem. We then analyze open-ended, odd-numbered chains, whose edge states pair up forming a triplet ground state. propose three experimental approaches that enable us to trigger control singlet-triplet spin transition. Two these are based on applying mechanical distortion chain. finally show transition can be controlled efficiently application an electric field.