Dataset for: Coexistence of Ferroelectricity and Metallicity in Weakly-coupled (SnSe)1.16(NbSe2) Crystal

The dataset comprises 4 xslx files. The "fig1-Excel.xlsx" file contains 3 tables, table "fig1-A" provides XRD intensity of (SnSe)1.16(NbSe2) and NbSe2 crystals; table "fig1-E" provides temperature-dependent resistivity along in-plane and cross-plane; table "fig1-F" provides temperature-dependent carrier density measured by Hall effect along in-plane. The "fig2-Excel.xlsx" file contains 6 tables, table "fig2-A" provides bias-dependent lateral PFM amplitude and phase hysteretic loops of (SnSe)1.16(NbSe2) measured at 300 K; table "fig2-D" provides SHG spectra of (SnSe)1.16(NbSe2) sheet under various excitation powers; table "fig2-E" provides SHG rotational patterns for parallel and perpendicular polarizations; table "fig2-F" and table "fig2-G" provide temperature-dependent SHG intensity and enthalpy changes of DSC; table "fig2-H" provides comparative survey of various systems with coexisting polarity/ferroelectricity and metallicity. The "fig3-Excel.xlsx" file contains 3 tables, table "fig3-A" provides STS spectrum of (SnSe)1.16(NbSe2) at 4.2 K; table "fig3-E" provides photon energy dependence of energy distribution curves passing through ARPES cuts along the Γ-Μ direction at k// =0.8 Å^-1^; table "fig3-F" provides Raman spectra of (SnSe)1.16(NbSe2) under 532 nm excitation at 300 K. The "fig4-Excel.xlsx" file contains 5 tables, table "fig4-B" provides hysteresis I–V loops demonstrating memristive behaviors under different bias sweep ranges; table "fig4-C" provides reversible current switching driven by applying positive and negative voltage pulses of ±0.3 V; table "fig4-D" provides memristive resistance loop measured at a read voltage (Vread) of ~100 mV after applying a stepwise poling voltage pulse; table "fig4-E" provides conductance modulation during potentiation and depression of in-plane ferroelectric memristor via an incremental pulse scheme; table "fig4-F" provides memristive retention characteristics with positive or negative voltage pulses of ±0.5 V pulse.