With weaker basic oxygen atoms it demonstrates the blue-shifting H-bond accompanied by CH band intensity decrease and a high frequency shift of bending vibrations.
In this paper, vibration modes with high frequency shift due to a small mass perturbation of 0.74 ng are analyzed.
The charge-transfer interaction between the pyrene derivative and porous graphene is evidenced by a high frequency shift of the G band of Raman spectrum, appearance of a new optical absorption band, and the increase in electrical conductivity.
The CF2 signal of the VDF chain sequence and the CHF signal at the head-to-head linkage of VDF TrFE sequence showed higher frequency shift in the temperature range 43 92 °C, whereas no change was found for the CHF signal at the head-to-tail linkage of VDF TrFE up to 92 °C.
This high frequency shift of νC-O phenolic band confirms the formation of covalent bond between oxygen atom of phenolic –OH and metal ion through deprotonation [12].
The three resonances can be assigned as follows: the high frequency shift corresponds to O3 layer protons (H2), while the two lower frequency shifts arise due to two types of configurations of O2 layer protons (H1) with shorter and longer H···O (hydrogen bond) distances and a difference in O H···O angles.
In addition to the requirement of the low squeeze damping, high frequency shifts or sensitivities is necessary for accurate measurement.
It is based on the single-sideband suppressed carrier electro-optic modulator frequency shifter that enables high frequency shifts to be realised in a frequency shifting amplified recirculating delay line loop structure.
Because they can achieve very high frequency shifts when very small masses are added to their surfaces, carbon nanotubes (CNTs) are considered as the most promising material candidate that can be used in designing mass sensors.
The use of even heavier molecules or nanoparticles for mass amplification should allow higher frequency shifts per amount of target substance and promises to extend the measurement range of QCMs into the sub-nanogramm region.
