Satoshi Motohiro

Perturbation-facilitated optical-optical double resonance spectroscopy of the h0u−(3P1) and H1u(3P1) ion-pair states of I2

Perturbation-facilitated optical-optical double resonance spectroscopy has been applied to study the h0u−(3P1) and H1u(3P1) ion-pair states of I2 correlating with I−(1S)+I+(3P1). The intermediate states used were the g/u parity mixed states found in the B 3∏(0u+)−X 1∑g+ absorption spectrum near the dissociation limit. We identified several B 3∏(0u+)∼3∏(0g−) coupled states by hyperfine interactions for the first time. These states had the 0u+ and 0g− double-faced character and facilitated to combine the X 1∑g+ ground state with the h0u−(3P1) state in the (1+1) photon excitation scheme following the optical selection rules for one-photon transition. We also accessed the H1u(3P1) state through the B 3∏(0u+)∼c1g mixed state, and elucidated the heterogeneous coupling between the h0u−(3P1) and H1u(3P1) states. Our analyses covered the region of about 48 200 to 50 300 cm−1, and gave the molecular parameters of the h0u−(3P1) state valid for v=0–17 and those of the H1u(3P1) state for v=0–20. The 3∏(0g−) state used...

Analysis of the 0g−(3P1)–B ′3 Π(0u−) system of I2 by perturbation-facilitated optical–optical double resonance

We present the analysis of the 0g−(3P1)–B ′3Π(0u−) system of I2. Both of the states are optically forbidden to access from the X 1Σg+ ground state, and the perturbation-facilitated optical–optical double resonance technique is used to access the 0g−(3P1) ion-pair state in the stepwise excitation. The intermediate states we used are the B 3Π(0u+)∼(3)0u− states coupled by hyperfine interaction, which are identified in the high vibrational levels of the B 3Π(0u+) state near the dissociation limit. These coupled states have the mixed character of the 0u+ and 0u− states, and allow to combine the X 1Σg+ ground state with the 0g−(3P1) state in the (1+1) photon excitation following the optical selection rules for one photon transition: 0g−(3P1)←(3)0u−∼B 3Π(0u+)←X 1Σg+. We elucidate the B 3Π(0u+)∼(3)0u− coupling scheme in the intermediate states by analyzing the second step of double resonance. The 0g−(3P1) state is located on the absolute energy axis and its molecular constants are reported. The B ′3Π(0u−) valenc...