There are several journals and publications that focus on the coordination chemistry for the UPSC optional subject. These resources provide valuable information and research findings in the field of coordination chemistry, which is an important topic within the UPSC syllabus.

Here are some notable journals and publications that specialize in coordination chemistry:

1. Inorganic Chemistry: This journal covers various aspects of inorganic chemistry, including coordination chemistry. It publishes research papers, reviews, and communications on topics related to the synthesis, structure, properties, and reactions of coordination compounds.

2. Journal of Coordination Chemistry: This journal specifically focuses on coordination chemistry and publishes original research articles, reviews, and short communications in the field. It covers various sub-disciplines of coordination chemistry, such as ligand design, metal-ligand interactions, and catalysis.

3. Coordination Chemistry Reviews: This journal provides comprehensive reviews and critical assessments of the latest advancements in coordination chemistry. It covers topics like coordination modes, metal-ligand bonding, and applications of coordination compounds in different fields.

4. Dalton Transactions: This journal publishes research articles, perspectives, and communications in all areas of inorganic chemistry, including coordination chemistry. It features studies on the synthesis, characterization, and reactivity of coordination compounds, as well as their applications in various fields.

5. Polyhedron: This journal focuses on the synthesis, structure, and properties of coordination compounds. It publishes research papers, reviews, and short communications in the field of coordination chemistry, highlighting the diverse applications of these compounds.

6. Chemical Society Reviews: Although not exclusively focused on coordination chemistry, this journal covers a wide range of topics in chemistry, including coordination chemistry. It publishes critical reviews that summarize and analyze the latest developments in the field.

These journals and publications provide a wealth of information and research findings that can be valuable for UPSC aspirants preparing for the optional subject of coordination chemistry. It is recommended to regularly refer to these publications to stay updated with the latest advancements in the field and to gain a deeper understanding of the subject.