Carbon bonds (C-bonds) are the highly directional noncovalent interactions between carbonyl-oxygen acceptors and sp3 -hybridized-carbon σ-hole donors through n→σ* electron delocalization. We have shown ubiquitous existence of C-bonds in proteins with help careful protein structure analysis quantum calculations, precisely determined C-bond energies. The importance conventional such as hydrogen bond (H-bonds) halogen (X-bonds) function biological molecules well established, while carbon still...

Gas-phase vibrational spectroscopy, coupled cluster (CCSD(T)), and dispersion corrected density functional (B97-D3) methods are employed to characterize surprisingly strong sulfur center H-bonded (SCHB) complexes between cis trans amide NH S atom of methionine cysteine side chain. The N-H···S H-bonds compared with the representative classical σ- π-type such as N-H···O, N-H···O═C N-H···π H-bonds. With spectroscopic, theoretical, structural evidence, found be σ-type H-bonds, despite smaller...

Careful protein structure analysis unravels many unknown and unappreciated noncovalent interactions that control structure; one such unrecognized interaction in is selenium centered hydrogen bonds (SeCHBs). We report, for the first time, SeCHBs involving amide proton of selenomethionine (Mse), i.e., amide–N–H···Se H-bonds discerned proteins. Using mass selective conformer specific high resolution vibrational spectroscopy, gold standard quantum chemical calculations at CCSD(T), in-depth...

Thioamides are used as potential surrogates of amides to study the structure and dynamics proteins nucleic acids. However, incorporation thioamides in biomolecules leads changes their structures conformations mostly attributed strength amide-N-H···S═C hydrogen bond. In most cases, it is considered weak owing small electronegativity sulfur, some strong conventional H-bonds. Herein, adopting PDB analysis, NMR spectroscopy, quantum chemistry calculations, we have shown that a geometrical...

In addition to N–H⋯OC bonds, less conventional N–H⋯S hydrogen bonds are found stabilize extended backbone geometries in derivatives of a thietane α-amino acid, providing promising tool for the design new peptidomimetic architectures.

In 4-membered ring heterocyclic α-amino acid derivatives, extended conformations based on intraresidue C5 H-bonds can be stabilized by N–H⋯X H-bonds, making the combined C5–C6γ structures prominent in both gas phase and weakly polar solutions.

Abstract Carbon bonds (C‐bonds) are the highly directional noncovalent interactions between carbonyl‐oxygen acceptors and sp 3 ‐hybridized‐carbon σ‐hole donors through n→σ* electron delocalization. We have shown ubiquitous existence of C‐bonds in proteins with help careful protein structure analysis quantum calculations, precisely determined C‐bond energies. The importance conventional such as hydrogen bond (H‐bonds) halogen (X‐bonds) function biological molecules well established, while...

Nowadays, piezoelectric materials have found various applications in fields like energy harvesting, precision mechanics and life sciences. In this regard organic molecules their crystals are not explored detail to be used as an alternative source for materials. Piezo-coefficients of different H-bond cluster were calculated. It was that Sulfur Centered Hydrogen Bond (SCHB) complexes the optimum hydrogen bond strength dipole moment derivative achieving maximum piezo-response among systems...

Abstract The non‐toxic, environment friendly, biodegradable properties and cost effectiveness of active pharmaceutical ingredients (APIs) allow them to be used as green‐solvents for several applications. presence multiple binding sites in the APIs has an additional advantage flue gas capture. Herein we report a detailed analysis efficient SO 2 capture by anions associated with through strong weak non‐covalent interactions. DFT studies Langmuir adsorption model suggest that based are highly...

The interaction of polycyclic aromatic hydrocarbons (PAHs) with vacuum ultraviolet (VUV) photons triggers the emission well-known infrared bands (AIBs) but other mechanisms such as fragmentation can be involved in this interaction. Fragmentation leads to selection effects that favor specific sizes and structures. We investigate impact aliphatic bonds on VUV photo-stability PAH cations under conditions applicable for photodissociation regions (PDRs). Cations pyrene (C16H10) coronene (C24H12)...

The side-chain of methionine residues is long enough to establish NH⋯S H-bonds with neighboring carbonyl groups the backbone, giving rise so-called intra-residue 6δ and inter-residue 7δ H-bonds. aim present article document how substitution sulfur a selenium atom affects H-bonding Met system. This was investigated both experimentally theoretically by conformation-resolved optical spectroscopy, following an isolated molecule approach. work emphasizes similarities Sem in terms conformational...

A dual microwave and optical spectroscopic study of a capped cysteine amino acid isolated in supersonic expansion, combined with quantum chemistry modelling, enabled us to access the conformational preferences Cys embedded protein chain.

The growing volume of plastics derived from electronic waste (e-waste) underscores the imperative for environmentally sustainable strategies management this waste. In light paramount importance issue, a pilot demonstrator decontamination polymers containing Brominated Flame Retardants (BFRs) has been developed. objective is to investigate potential decontaminating BFR-containing e-waste via UV-visible irradiation using rotatory laboratory operating under primary vacuum conditions. This...

Present work reports significantly high levels of ionization, eventually leading to Coulomb explosion Tetramethyl silane (TMS) clusters, on interaction with laser pulses intensity ∼109 W/cm2. prepared by supersonic expansion were photoionized at 266, 355 or 532 nm and the resultant ions detected using time-of-flight mass spectrometer. It is observed that wavelength irradiation size cluster are crucial parameters which drastically affect nature charge species generated upon photoionization...

The δ conformation is a local secondary structure in proteins that implicates πamide N-H⋯N interaction between backbone N atom and the NH of following residue. Small-molecule models thereof have been limited so far to rigid proline-type compounds. We show here derivatives cyclic amino acid with sulphur γ-position, specific side-chain/backbone N-H⋯S interactions stabilize sufficiently allow it compete classical C5 C7 H-bonded conformers.

Electron Beam (EB) irradiation was utilized to decontaminate model systems of industrial polymers that contain a brominated flame retardant (BFR). Acrylonitrile-butadiene-styrene (ABS) and Polycarbonate (PC) are two types commonly found in Waste Electrical Electronic Equipment (WEEE). In this study, these were exposed EB degrade DecaBromoDiphenylEther (DBDE), one the most toxic BFRs. Fourier-transform infrared spectroscopy analysis demonstrated an 87% degradation rate DBDE for ABS-DBDE...

Models of asparagine-containing dipeptides specifically designed to favor intrinsic folding into an Asx turn were characterized both theoretically, by using quantum chemistry, and experimentally, laser spectroscopy in the gas phase. Both approaches provided evidence for spontaneous Asn-Ala Asn-Gly dipeptide models most stable turn, a conformation stabilized C10 H-bond that was very similar type II' β-turn. In parallel, analysis turns implicating asparagine crystallized protein structures...

Mn^III(salen)(OH₂)₂⁺ undergoes reversible anation by HOX⁻<italic>via I</italic>_a mechanism followed proton controlled electron transfer involving Mn^III(salen)(HOX) and H₂OX.

Water exchange of <italic>trans</italic>-[Mn^III(salen)(OH₂)₂]⁺ studied by line broadening ¹⁷OH₂ NMR discloses its mechanism as associative interchange (<italic>I</italic>_a).

Models of protein chains containing a seleno-cysteine (Sec) residue have been investigated by gas phase laser spectroscopy in order to document the effect H-bonding properties SeH group folding Sec side chain, comparison with recent data on Ser- and Cys-containing sequences.

In order to protect human health and the environment, several regulations have been introduced in recent years reduce or even eliminate use of some brominated flame retardants (BFRs) due their toxicity, persistence bioaccumulation. Dispersions these BFRs polymers are widely used for various applications. this report, four different molecules, decabromodiphenyl ether (DBDE), hexabromocyclododecane (HBCDD), ethane (DBDPE) tris(tribromophenoxy)triazine (TTBPT), were dispersed solid matrix an...

Invited for the cover of this issue are David J. Aitken, Michel Mons, and co-workers at Université Paris-Saclay. The image depicts investigation strategies used to document intrinsic structures an important secondary structure in proteins, so-called Asx turn. Read full text article 10.1002/chem.202104328.