Multiserial Structure of Excitonic Energy Spectrum in Monoclinic ZnP2 Crystal

Abstract

One-photon excitonic absorption spectra of the monoclinic ZnP 2 b-ZnP 2 crystals are analysed. There exist four series characterized by the serial law E n E g À Ryan 2 Dan 3 with the same value of energy gap E g 1X6026 meV. By variational calculations of the exciton energy dependence on the anisotropy parameter, we conclude an appearance of several hydrogen-like series caused by the splitting of excitonic states with different quantum numbers l and jmj due to the low symmetry of the crystal. Conclusions are made that two series with D 0 can be attributed to the P-states of an exciton, and two others with D T 0 to the S-states of an exciton. Calculations of e±h exchange interaction in an S-exciton are performed. Splitting of the series with D T 0 is interpreted to have exchange origin (ortho±para-splitting). Its value is obtained to be 12.7 meV.

<title>Energy bands and Wannier-Mott excitons in Zn(P<formula><inf><roman>1-x</roman></inf></formula>As<formula><inf><roman>x</roman></inf></formula>)<formula><inf><roman>2</roman></inf></formula> and Zn<formula><inf><roman>1-x</roman></inf></formula>Cd<formula><inf><roman>x</roman></inf></formula>P<formula><inf>

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First-Principles DFT Insights into the Stabilization of Zinc Diphosphide (ZnP2) Nanocrystals via Surface Functionalization by 4-Aminothiophenol for Photovoltaic Applications

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Optical study of ZnP2 nanoparticles in zeolite Na–X

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