Giant Seebeck Effect of Dibenzo[g,p]chrysene and its Derivatives: Deuteration and Substituent Effects and Relationship with Interlayer Distance

Hirotaka Kojima; Kohei Kojima; Toshiki Kawauchi; Ryo Abe; Masakazu Nakamura; Masakazu Yamagishi; Naoto Hamaguchi; Katsunori Yamanishi; Hayato Tsuji

doi:10.1002/asia.202401692

Giant Seebeck Effect of Dibenzo[g,p]chrysene and its Derivatives: Deuteration and Substituent Effects and Relationship with Interlayer Distance

Chem Asian J. 2025 Jan 4:e202401692. doi: 10.1002/asia.202401692. Online ahead of print.

Authors

Hirotaka Kojima¹, Kohei Kojima², Toshiki Kawauchi², Ryo Abe³, Masakazu Nakamura², Masakazu Yamagishi⁴, Naoto Hamaguchi⁵, Katsunori Yamanishi⁵, Hayato Tsuji⁶

Affiliations

¹ National institute of Technology, Maizuru College, none, JAPAN.
² NAIST: Nara Sentan Kagaku Gijutsu Daigakuin Daigaku, Division of Materials Science, JAPAN.
³ Nara Institute of Science and Technology: Nara Sentan Kagaku Gijutsu Daigakuin Daigaku, Division of Materials Science, JAPAN.
⁴ National Institute of Technology, Toyama College, Department of Applied Chemistry and Chemical Engineering, JAPAN.
⁵ Kanagawa University: Kanagawa Daigaku, Department of Chemistry, JAPAN.
⁶ Kanagawa University, Department of Chemistry, JAPAN.

PMID: 39754605
DOI: 10.1002/asia.202401692

Abstract

Thermoelectric properties of undoped crystals of dibenzo[g,p]chrysene (DBC), deuterated DBC (DBC-d16), and 2,10-dimethyl-DBC (DBC-Me2) have been studied to obtain some insights into the relationship between the structural parameters of materials and the giant Seebeck effect. X-ray crystallography showed one-dimensional columnar packing with the interlayer distances (d) for DBC-d16, DBC, and DBC-Me2 were 3.78 Å, 3.79 Å, and 3.91 Å, respectively. All three compounds formed one-dimensional carrier transport pathways as suggested by the transfer integral calculations. Their Seebeck coefficients (α) were negative, indicating n-type behavior. DBC-d16 exhibited among the highest peak Seebeck coefficient (αmax = -114 mV/K) compared to DBC and DBC-Me2 (αmax = -31 and -22 mV/K, respectively). The power factors of DBC-d16 and DBC-Me2 were higher than that of DBC, due to an increase in Seebeck coefficient and conductivity, respectively. Notably, a positive correlation was found between the peak temperature of the Seebeck coefficient and interlayer distance d, while |αmax| correlated negatively with d. Deuteration significantly enhanced |αmax|, likely due to reduced molecular vibrations, though further investigation should consider the effect of dynamic structural fluctuation due to thermal motion.

Keywords: deuteration; dibenzochrysene; giant Seebeck effect; structure-property relationship; thermoelectric generators.