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In order to better understand the effect of non‐covalent weak interactions on molecules, we have explored a variety of weak interactions, such as improper H‐bonding (HB), tetrel bonds (TBs) and halogen bonds, in fluorinated chiral zinc complexes. High resolution neutron diffraction studies revealed a methylene carbon‐hydrogen bond elongation and shortening due to TB and improper HB interactions, respectively. To show the accumulative effects of multiple weak interactions on the C−H bond, three types of tetrel bonds have been carefully examined. We have also shown how C−H bond elongation can be easily offset by forming an improper HB with the H atom from this C−H bond. Non‐covalent interaction and electrostatic potential analysis investigations have been used to affirm the nature of the interactions based on density functional theory (DFT) and other related calculations. [ABSTRACT FROM AUTHOR]

The nitrogen-vacancy (NV) centers in diamond are among the most thoroughly investigated defects in solid-state matter; however, our understanding of their properties upon far-UV excitation of the host matrix is limited. This knowledge is crucial for the identification of NV as the carrier of extended red emission (ERE) bands detected in a wide range of astrophysical environments. Herein, we report a study on the photoluminescence spectra of NV-containing nanodiamonds excited with synchrotron radiation over the wavelength range of 125-350 nm. We observed, for the first time, an emission at 520-850 nm with a quantum yield greater than 20 %. Our results share multiple similarities with the ERE phenomena, suggesting that nanodiamonds are a common component of dust in space. [ABSTRACT FROM AUTHOR]

Much of the current understanding of thermal effects in biological systems is based on macroscopic measurements. There is little knowledge about the local thermostability or heat tolerance of subcellular components at the nanoscale. Herein, we show that gold nanorod-fluorescent nanodiamond (GNR-FND) hybrids are useful as a combined nanoheater/nanothermometer in living cells. With the use of a 594 nm laser for both heating and probing, we measure the temperature changes by recording the spectral shifts of the zero-phonon lines of negatively charged nitrogen-vacancy centers in FNDs. The technique allows us to determine the rupture temperatures of individual membrane nanotubes in human embryonic kidney cells, as well as to generate high temperature gradients on the cell membrane for photoporation and optically controlled hyperthermia. Our results demonstrate a new paradigm for hyperthermia research and application. [ABSTRACT FROM AUTHOR]