Mechanical strain and atomic polarizability are powerful levers for controlling van der Waals (vdW) interactions in low-dimensional nanostructures. By altering the lattice geometry or modifying the electronic response of individual atoms, one can effectively tune both the magnitude and asymptotic decay of interfragment forces. This work demonstrates that these parameters enable precise, reversible regulation of vdW interactions in 1D carbyne-like chains and 2D graphenic systems through their influence on many-body (MB) dipolar coherence.
In 1D carbyne chains, increasing the C–C bond length—induced by tensile strain—reduces interatomic coupling and weakens the collective dipole oscillations responsible for long-range attraction. As the lattice parameter increases from 1.2 Å to 1.4 Å, the dispersion of MBD mode bands diminishes, leading to a flatter excitation spectrum. This reduction in mode dispersion corresponds to a decrease in non-local response, resulting in faster power-law decay and shorter effective interaction range. The power law exponent P(R) increases in modulus, moving closer to the pairwise R⁻⁵ limit, especially at large separations. Conversely, compressing the chain enhances coupling, strengthens coherent charge fluctuations, and slows the decay, enabling longer-ranged interactions even at moderate distances.
The effect of strain is further amplified when combined with changes in atomic polarizability. The Tkatchenko–Scheffler (TS) method, which scales atomic polarizabilities according to Hirshfeld volumes, reveals that rescaling the bare polarizability by 0.87 relative to free-atom values provides an accurate description of low-dimensional systems. When this scaling is applied under strain, the resulting polarizability modulation directly impacts the strength of MB interactions.SOS1 ProteinStorage & Stability For instance, stretching the chain reduces effective polarizability per atom due to reduced orbital overlap, further weakening the interaction. However, doping with boron—a highly polarizable element—can counteract this effect by introducing enhanced local polarizability, partially restoring long-range coupling even under strain.
In 2D graphenic systems, strain also modulates vdW interactions, though the effects are more subtle due to isotropic coupling. Uniaxial or biaxial strain alters the band structure near the Brillouin zone center, modifying the dispersion of collective modes. Compressive strain tends to increase mode frequency and reduce coherence, accelerating decay. Tensile strain, conversely, lowers the minimum excitation energy and enhances long-wavelength fluctuations, promoting slower decay. These trends are consistent across different dopant concentrations and remain robust even after structural relaxation.KRAS ProteinSynonyms
Polarizability modulation via substitutional doping offers another route for control.PMID:35067061 Boron, with a static polarizability of 21 a.u., significantly increases the average response of the system compared to carbon (12 a.u.). In B-doped graphene, this leads to stronger low-frequency modes and extended charge oscillations, slowing the power-law decay and enhancing binding energy. Nitrogen, with lower polarizability (7.4 a.u.), has the opposite effect: it suppresses collective modes and accelerates decay. Notably, the impact of doping persists over long ranges—up to 15 nm—indicating that the tuning mechanism is not limited to short-scale phenomena.
Furthermore, the combination of strain and doping allows for synergistic control. For example, applying tensile strain to a B-doped chain may initially weaken the interaction due to reduced coupling, but the high intrinsic polarizability of B atoms maintains a significant degree of coherence. This results in a net enhancement of long-range attraction compared to undoped strained chains.
These findings highlight that strain and polarizability are not merely geometric or chemical parameters—they are active tools for engineering the quantum response of nanoscale systems. By manipulating them, one can shift the balance between localized and delocalized interactions, switch between short- and long-range dominance, and fine-tune binding strength without changing molecular identity. This capability is crucial for designing adaptive materials, responsive coatings, and self-assembling architectures where dynamic control over intermolecular forces is essential. Ultimately, this work establishes a new paradigm: the van der Waals force is not fixed by nature, but malleable through intelligent design of electronic structure and mechanical environment.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com