TY - JOUR

T1 - Evolution of Structures and Optical Properties in a Series of Infrared Nonlinear Optical Crystals LixAg1-xInSe2 (0 ≤ x ≤ 1)

AU - Isaenko, Lyudmila

AU - Dong, Linfeng

AU - Korzhneva, Ksenia

AU - Yelisseyev, Alexander

AU - Lobanov, Sergey

AU - Gromilov, Sergey

AU - Molokeev, Maxim S

AU - Kurus, Alexey

AU - Lin, Zheshuai

N1 - This work was supported by the National Natural Science Foundation of China (Grant No. 22133004), Russian Science Foundation, grant # 19-12-00085-P (crystal growth, crystal structure analysis, band gap measurement), Ministry of Education and Science of the Russian Federation, grant FSUS-2020-0036 (SHG coefficients measurements), and partly done on state assignment of IGM SB RAS No. 122041400031-2 (composition chemical analysis).

PY - 2023/10/2

Y1 - 2023/10/2

N2 - In this work, a number of new infrared nonlinear optical (NLO) crystals of LixAg1-xInSe2, in which the ratio x of Li/Ag varies in a wide range from 0 to 1, are investigated. Structural analysis reveals that the space group of LixAg1-xInSe2 evolved from I4̅2d in AgInSe2 to Pna21 in LiInSe2 as x increases from low values (0, 0.2, 0.37) to large values (0.55, 0.78, 0.81, 1). Compared to other Li/Ag coexisting chalcogenides such as LixAg1-xGaS2 and LixAg1-xGaSe2, the structural distortions in LixAg1-xInSe2 are much more prominent. This may explain the limited crystallization region in the phase graph of the tetragonal structure LixAg1-xInSe2. The fundamental optical absorption edges in these LixAg1-xInSe2 compounds are determined from the direct electronic transitions and the band gaps Eg gradually increase as the lithium content increases, consistent with the first-principles calculations. The composition x = 0.78 is calculated to have a good set of optical properties with a large NLO coefficient (dpowder = 28.8 pm/V) and moderate birefringence (Δn ∼ 0.04). Accordingly, the Li0.78Ag0.22InSe2 crystal is grown by the modified Bridgman-Stockbarger method, and it exhibits a wide transparency range from 0.546 to 14.3 μm at the 2% transmittance level.

AB - In this work, a number of new infrared nonlinear optical (NLO) crystals of LixAg1-xInSe2, in which the ratio x of Li/Ag varies in a wide range from 0 to 1, are investigated. Structural analysis reveals that the space group of LixAg1-xInSe2 evolved from I4̅2d in AgInSe2 to Pna21 in LiInSe2 as x increases from low values (0, 0.2, 0.37) to large values (0.55, 0.78, 0.81, 1). Compared to other Li/Ag coexisting chalcogenides such as LixAg1-xGaS2 and LixAg1-xGaSe2, the structural distortions in LixAg1-xInSe2 are much more prominent. This may explain the limited crystallization region in the phase graph of the tetragonal structure LixAg1-xInSe2. The fundamental optical absorption edges in these LixAg1-xInSe2 compounds are determined from the direct electronic transitions and the band gaps Eg gradually increase as the lithium content increases, consistent with the first-principles calculations. The composition x = 0.78 is calculated to have a good set of optical properties with a large NLO coefficient (dpowder = 28.8 pm/V) and moderate birefringence (Δn ∼ 0.04). Accordingly, the Li0.78Ag0.22InSe2 crystal is grown by the modified Bridgman-Stockbarger method, and it exhibits a wide transparency range from 0.546 to 14.3 μm at the 2% transmittance level.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85174281189&origin=inward&txGid=763ee3bc922a08a55a6993cbd738f623

U2 - 10.1021/acs.inorgchem.3c01993

DO - 10.1021/acs.inorgchem.3c01993

M3 - Article

C2 - 37728539

VL - 62

SP - 15936

EP - 15942

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

IS - 39

ER -