Your starting point is reading tonnes of papers about your topic and in the type of journals you're targeting. You're already to good start.
A research paper conveys a key message to target audience and highlights the key contribution to the body of knowledge. It is not as broad as a Thesis.
Hence, in drafting a research paper, one needs to figure out and be clear in their mind ... what's the message I'm putting out there, what's significant about the work done, what's the purpose.
In your instance as you've narrated, you've got ideas already. Storyboard them and write them down.
Your results, itemise them and write them down. Also, write how you went about getting the results you've gotten. Slowly, the research paper is taking shape. With more ingredients, the paper is 'cooked', ready your 'dishing'.
There're different structures for research papers across different fields. For chemistry modelling, you should broadly fall under the IMRaD model.
I'll talk a bit more on this, before then take a look for instance at this GEOS-Chem chemistry model v10 by Keller and Evans (2019).
They have a structure introducing their work, the method used, deep dive into the work, followed by discussion and then conclusion.
1) Introduction;
2) Methods;
3) Long-term simulation using the random;
forest model;
4) Discussion;
5) Conclusions.
[Extract from IMRaD Wikipedia]
Introduction – Why was the study undertaken? What was the research question, the tested hypothesis or the purpose of the research?
Methods – When, where, and how was the study done? What materials were used or who was included in the study groups (patients, etc.)?
Results – What answer was found to the research question; what did the study find? Was the tested hypothesis true?
Discussion – What might the answer imply and why does it matter? How does it fit in with what other researchers have found? What are the perspectives for future research?
Please note that some have literature review (related works) as part of Introduction or better still just after introduction and before methods.
The literature review is rapid or purposeful. It's different from systematic review. However, some chemistry modelling papers are actually chemistry modelling reviews in which case they might be systematic review (aligning with PRISMA) or narrative review or even rapid following the PRISMA-ScR.
Also, take note that in some fields, methodology covers not just the methods, but the philosophical underpinning, research approach and strategy, methods and data collection tools. See the research onion in Saunders et al. (2023), now in the 9th edition.
Saunders, M., Lewis, P., & Thornhill, A. (2023). Research Methods for Business Students. (9th ed.) Pearson