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Inelastic Tunneling Current-Driven Motions of Single Adsorbates
Published in Tamar Seideman, Current-Driven Phenomena in Nanoelectronics, 2016
H. Ueba, S. G. Tikhodeev, B. N. J. Persson
Recently Kumagai et al.75 observed hydrogen-bond exchange reaction in a water dimer (H(D)2O)2 on a Cu(110) surface. The bias-independent interchange rate below 40 meV, which is about 60 times higher for (H2O)2 than for (D2O)2, suggests the intrinsic quantum tunneling in the vibrational ground states in the double potential wells along the interchange reaction pathway. The rate exhibits an increase above the bias voltage at 45 meV for (H2O)2 and 41 meV for (D2O)2, respectively. The linear dependence of the rate for (H2O)2 at 54 meV on tunneling current also suggests the vibrationally-assisted tunneling from the first vibrational excited state of the intermolecular mode that correlates with the reaction coordinate, because of the larger potential barrier (0.24 eV) than the
Dimers and trimers of HF, H2O, NH3 and CH4 with N2. Ab initio studies on structures and vibrational frequencies
Published in Molecular Physics, 2021
After the first quantum mechanical treatment of the water dimer by Morokuma and Pedersen in 1968 [26], a large number of theoretical articles using various methods have been published. From potentials with flexible monomers LeForestier et al [27] obtained the ‘correct’ De of 21.0 kJ/mol, or 1760 cm−1, for the water dimer. Lane et al. [28] calculated a counterpoise corrected De of 20.85 kJ/mol, or 1743 cm−1, using the CCSD(T)-F12b/aug-cc-pVQZ/aug-cc-pV5Z method extrapolated to the CBS limit. Rappé and Bernstein [29] performed ab initio calculations using various methods and basis sets on dimeric complexes of water, ammonia and methane. Their MP2/cc-pV5Z dissociation energy for the water dimer is 1678 cm−1. The CCSD(T) value for the water dimer obtained here is 1702 cm−1 (Table 5), whereas the MP2 result (Fig. S3 in Supplement) is 1730cm−1 (Table 6).
Analysis of the interactions in FCCF:(H2O) and FCCF:(H2O)2 complexes through the study of their indirect spin–spin coupling constants
Published in Molecular Physics, 2018
María Cristina Caputo, Ibon Alkorta, Patricio F. Provasi, Stephan P. A. Sauer
The binding energy, see Table 1, of the three minima is in a range of only 2 kJ/mol (between −33.4 and −35.6 kJ mol−1) being D the most stable one and E and F the least ones. The MBIE results (Table S4) indicate that the most stabilising two-body term corresponds to the water dimer interaction with energies around −25 kJ mol−1. The two-body terms due to the interaction of the water molecules with FCCF range between −3.8 and −5.7 kJ mol−1. The three-body term, which is associated with the cooperativity, shows negative values for D and F (−1.2 and −0.6 kJ mol−1) and positive for E (0.5 kJ mol−1).