The crystalline structure refinement, chemical bond ionicity, and lattice energy were carried out for Zn(Ta1−xNbx)2O6 ceramics with tri‐α‐PbO2 structure to investigate the correlations between the crystalline structure, phase stability, bond ionicity, and microwave dielectric properties. The chemical bond ionicity and lattice energy of the ZnTa2O6 system were calculated and evaluated using a semiempirical method based on the dielectric description theory proposed by Phillips, Van Vechten, and Levine (P–V–L theory). The crystalline structure stability varied with the content of Nb5+ ion resulted in the lattice energy decrease. The increase of Ta/Nb–O bond ionicity was observed in the crystalline structure, which should be main contribution to electric polarization. The dielectric properties of the Zn(Ta1−xNbx)2O6 ceramics were strongly dependent on the chemical bond ionicity of Ta/Nb–O bond with tri‐α‐PbO2 structure.

Single-phase white phosphors could overcome many drawbacks of traditional phosphors, and warm white light phosphors have been considered suitable for indoor illumination applications. Thus, synthesizing new single-phase warm white phosphors is significant for the production of LEDs. Based on the above considerations, a novel single component warm white light phosphor SmxTbyDy0.2-x-y-metal organic frameworks (MOFs) has been prepared successfully in this study. The compound Sm0.1Tb0.04Dy0.06-MOF shows ideal warm white light emission with CIE coordinates (0.333, 0.3522), a color rendering index (CRI) value of 86.7, a low correlated color temperature (CCT) value of 4444 K, and good heating/cooling circulation. In addition, the LED devices fabricated with this novel warm white light phosphor have excellent warm white light quality even at high temperatures, which is necessary for its practical application.

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