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Liu et al. J. Mater. Inf. 2025, 5, 27  I http://dx.doi.org/10.20517/jmi.2024.105  Page 3 of 18

               ally an artificial neural network) to decode the representation from descriptor to the potential energy. One
               notable example is the LASP software [21]  with its neural network potential constructed by the power-type
               structural descriptors represented by atom-centered symmetry functions [22] developed by Huang et al., which has been
               widely utilized in computational simulation for various heterogeneous catalysis topics. For instance, in the
               ethene epoxidation reaction on silver [23] , they identified the O 5 phase as highly active. Moreover, the calcu-
               lated selectivity and ethene conversion are consistent with experimental results. In the case of the Fe-FTS
               system, Liu et al. showed that surface reconstructions of iron carbides under a typical FTS gas atmosphere
               are significant and usually involve the relocation of surface carbon atoms [24] . They demonstrated that the A-
               P5 site, a pentagon configuration consisting of five iron atoms and a carbon atom bonded to four of the iron
               atoms, is abundant on several active surfaces of iron carbides as an active site for CO dissociation and C-C
               coupling [25] . Their obtained product yield also shows good agreement with experiments [26] . Another well-
               known example is the DeePMD-kit software [27–30]  with its deep potential (DP) method using an end-to-end
               symmetry-preserving structural descriptor consisting of smooth internal coordinates and embedding network
               transformation for encoding local atomic environment [27,31] , widely used for atomistic simulation including
               the dynamics of growing carbon nanotube interfaces [32] , the sintering of Au nano-particles on supports having
               different metal affinities [33] , the size effects of supported Au catalysts for CO oxidation activity [34] , CO adsorp-
               tion induced surface reconstruction dynamics on the Cu surfaces [35] , and structural/compositional evolution
               of Pd(111) surfaces for CO oxidation under varying adsorption coverages [36] .


               Despite numerous successes of MLPs in atomistic simulations, their applications often face economic and
               scalability limitations. The most obvious one is that all of the data used for training and validating MLPs are
               generated from scratch, namely, by ab initio molecular dynamic (AIMD) simulation or other simulation meth-
               ods with ab initio calculation (typically DFT). Efficient data generation platforms through an active learning
               procedure such as DP GENerator (DP-GEN) [37]  or Generating DP with Python (GDPy) [38]  can significantly
               facilitate this process. However, a substantial amount of effort is still needed to construct DFT-labeled datasets,
               especially for heterogeneous catalysis domain due to its complexity with characteristics of bulks, surfaces, and
               adsorbates altogether. The publicly available large datasets, such as OC20 [39] , OC22 [40] , and MPtrj [41] , have
               covered extensive physical and chemical knowledge, becoming very useful for overcoming the challenges of
               data generation. However, traditional MLPs usually struggle to generalize to applications not covered by the
               training data, especially when additional elements and structural configuration are included in the simulation
               tasks, making them poor at combining and utilizing the knowledge from these multiple and large datasets
               together due to the varying ab initio calculation methods employed in different datasets and the vast compo-
               sitional space contained across all these datasets.


               Recently, the rise of “universal” or “fundamental” MLPs offers opportunities for addressing the issues above
               and greatly extending the application scope of MLPs, often referred to as large atomic models (LAMs). One
               remarkable advancement in LAM is the second version of the deep potential with attention pre-trained model
               (DPA-2)developedbyZhangetal. fromtheDeepModelingopen-sourcecommunity  [42,43] . Thismodelutilizes
               unified descriptors constructed by deep neural network architecture, and uses the multi-task pre-training strat-
               egy to jointly pre-train a multi-head model using multiple datasets that encompass multidisciplinary knowl-
               edge from a broad range of application domains. By fine-tuning for specific downstream tasks, the pre-trained
               DPA-2 model can be efficiently deployed to evaluate the potential energy surface (PES) of a specific research
               domain with precision and generalization.


               In this work, we have developed an MLP based on the pre-trained DPA-2 model by fine-tuning methodology,
               named fine-tuned Fischer-Tropsch deep potential (FT DP), which aims to describe the global chemical space
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               consisting of Fe-C-H-O compositions in an accurate and extendable way, enabling us to perform efficient
               computational simulation to investigate the characteristics of Fe-FTS systems. This paper is organized as fol-
               lows. In the next section, we present theoretical schemes and computational settings used in this work. In the
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