Connecting effect on the first hyperpolarizability of armchair carbon–boron–nitride heteronanotubes: pattern versus proportion. Issue 20 (6th May 2016) - Zhong, Rong-Lin
Abstract : The first hyperpolarizability of the carbon–boron–nitride heteronanotube models is significantly dependent on the connecting patterns and carbon proportions. Abstract : Carbon–boron–nitride heteronanotubes (BNCNT) have attracted a lot of attention because of their adjustable properties and potential applications in many fields. In this work, a series of CA, PA and HA armchair BNCNT models were designed to explore their nonlinear optical (NLO) properties and provide physical insight into the structure–property relationships; CA, PA and HA represent the models that are obtained by doping the carbon segment into pristine boron nitride nanotube (BNNT) fragments circularly around the tube axis, parallel to the tube axis and helically to the tube axis, respectively. Results show that the first hyperpolarizability ( β 0 ) of an armchair BNCNT model is dramatically dependent on the connecting patterns of carbon with the boron nitride fragment. Significantly, the β 0 value of PA-6 is 2.00 × 10 4 au, which is almost two orders of magnitude larger than those (6.07 × 10 2 and 1.55 × 10 2 au) of HA-6 and CA-6. In addition, the β 0 values of PA and CA models increase with the increase in carbon proportion, whereas those of HA models show a different tendency. Further investigations on transition properties show that the curved charge transfer from N-connecting carbon atoms to B-connecting carbon atoms of PA models is essentially the origin of the big difference among these models. This new knowledge about armchair BNCNTs may provide important information for the design and preparation of advanced NLO nano-materials.