Niels Bohr constructed the first version of quantum mechanics. It has been called “old quantum mechanics” with a connotation of being obsolete. It is logically consistent, however, and deserves the name of simple qu...Niels Bohr constructed the first version of quantum mechanics. It has been called “old quantum mechanics” with a connotation of being obsolete. It is logically consistent, however, and deserves the name of simple quantum mechanics (SQM). It differs only from the semiclassical approximation by assuming that the average position and average velocity of an electron can be sharply defined on closed orbits. This assumption does not contradict Heisenberg’s uncertainty relations, since the quantization rule means that the electron can be anywhere on this orbit when it allows for stationary waves. This approach was remarkably efficient for one electron in hydrogen atoms and even for the electron pair in hydrogen molecules. However, dissociation of H2 and determination of the orbit of the single electron in H2+led to problems that remained unsolved for more than 100 years. Their solution, presented here, yields more physical insight and reveals, for instance, that mutual polarization of two hydrogen atoms can yield a metastable state.展开更多
The interaction of 2-methyl-1,4-naphthoquinone (MQ) with nucleotides and DNA have been studied using KrF laser photolysis aimed at elucidation of the initial reaction mechanism. Laser spectroscopy demonstrates directl...The interaction of 2-methyl-1,4-naphthoquinone (MQ) with nucleotides and DNA have been studied using KrF laser photolysis aimed at elucidation of the initial reaction mechanism. Laser spectroscopy demonstrates directly that the initial species from interaction of MQ with nucleotides are radical canons of nucleotides and MQ radical anion. Kinetic analysis indicates that formation of ion pair from interaction of any of mucleotides with MQ is synchronous with decay of triplet MQ, which has provided dynamic evidence for initiation of election transfer from DNA bases to triplet MQ, while the oxidation of TMP with slowest rate could be the rate determining step during the interaction of triplet MQ with DNA. Moreover direct observation of stabilized DNA guanyl radical canon from interaction of MQ with DNA has provided initial evidence for selective cleavage of DNA at guanine moiety, which has simulated the major, initial species produced by the action of ionizing radiation or UV light on DNA.展开更多
The intramolecular electronic communication and multilevel ion-pairing effect of triferrocenylmethane（TriFcM） in organic phase was studied with the ＂thin-layer electrochemistry＂ approach.Three pairs of symmetric p...The intramolecular electronic communication and multilevel ion-pairing effect of triferrocenylmethane（TriFcM） in organic phase was studied with the ＂thin-layer electrochemistry＂ approach.Three pairs of symmetric peaks in cyclic voltammetry of TriFcM correspond to three one-electron electrochemical reaction processes and indicate strong intramolecular electronic communication,which could be used to study the multilevel ion-pairing effect.Three different formation constants of ion-pairs between the three ferroceniums of TriFcM and perchlorate in thin organic film were obtained and compared.展开更多
ELECTRON transfer (ET) reaction is concerned with many important processes in chemistry and biology, and has become an active research field in recent years. According to Marcus’s theory, the ET rate can be expressed...ELECTRON transfer (ET) reaction is concerned with many important processes in chemistry and biology, and has become an active research field in recent years. According to Marcus’s theory, the ET rate can be expressed as the Fermi’s golden rule:展开更多
文摘Niels Bohr constructed the first version of quantum mechanics. It has been called “old quantum mechanics” with a connotation of being obsolete. It is logically consistent, however, and deserves the name of simple quantum mechanics (SQM). It differs only from the semiclassical approximation by assuming that the average position and average velocity of an electron can be sharply defined on closed orbits. This assumption does not contradict Heisenberg’s uncertainty relations, since the quantization rule means that the electron can be anywhere on this orbit when it allows for stationary waves. This approach was remarkably efficient for one electron in hydrogen atoms and even for the electron pair in hydrogen molecules. However, dissociation of H2 and determination of the orbit of the single electron in H2+led to problems that remained unsolved for more than 100 years. Their solution, presented here, yields more physical insight and reveals, for instance, that mutual polarization of two hydrogen atoms can yield a metastable state.
文摘The interaction of 2-methyl-1,4-naphthoquinone (MQ) with nucleotides and DNA have been studied using KrF laser photolysis aimed at elucidation of the initial reaction mechanism. Laser spectroscopy demonstrates directly that the initial species from interaction of MQ with nucleotides are radical canons of nucleotides and MQ radical anion. Kinetic analysis indicates that formation of ion pair from interaction of any of mucleotides with MQ is synchronous with decay of triplet MQ, which has provided dynamic evidence for initiation of election transfer from DNA bases to triplet MQ, while the oxidation of TMP with slowest rate could be the rate determining step during the interaction of triplet MQ with DNA. Moreover direct observation of stabilized DNA guanyl radical canon from interaction of MQ with DNA has provided initial evidence for selective cleavage of DNA at guanine moiety, which has simulated the major, initial species produced by the action of ionizing radiation or UV light on DNA.
基金the NSFC(No.21173023)the 111 Project(No.B07012) in China and the TriFcM provided from professor Hua-Zhong Yu at Simon Fraser University in Canada
文摘The intramolecular electronic communication and multilevel ion-pairing effect of triferrocenylmethane（TriFcM） in organic phase was studied with the ＂thin-layer electrochemistry＂ approach.Three pairs of symmetric peaks in cyclic voltammetry of TriFcM correspond to three one-electron electrochemical reaction processes and indicate strong intramolecular electronic communication,which could be used to study the multilevel ion-pairing effect.Three different formation constants of ion-pairs between the three ferroceniums of TriFcM and perchlorate in thin organic film were obtained and compared.
文摘ELECTRON transfer (ET) reaction is concerned with many important processes in chemistry and biology, and has become an active research field in recent years. According to Marcus’s theory, the ET rate can be expressed as the Fermi’s golden rule:
