MediumWeightage: 4–6%~2 Q/paperUnit 12 of 20

Coordination Compounds — JEE Main Chemistry Syllabus 2026

Complete NTA official syllabus for Coordination Compounds in JEE Main Chemistry: 5 official topics,4 key formulas, weightage 4–6%, ~2 question(s) per paper, difficulty: Medium.

NTA Official Syllabus — 5 Topics
  1. 1Werner's theory, ligands and central atom
  2. 2IUPAC nomenclature of coordination compounds
  3. 3Isomerism: structural and stereoisomerism
  4. 4Bonding: VBT and Crystal Field Theory (CFT)
  5. 5Colour, magnetic behaviour and stability of complexes
Key Formulas — 4 Formulas

Coordination Compounds in JEE Main 2026 — Complete Overview

Coordination Compounds is Unit 12 of the JEE Main Chemistry syllabus as prescribed by the National Testing Agency (NTA). It carries a weightage of 4–6% and typically contributes approximately 2 question(s) per paper. Classified as a Medium-difficulty chapter, Coordination Compounds is a moderately challenging but highly scorable chapter. Students who prepare it systematically typically outperform 40–60% of their peers on these questions.

The official NTA syllabus for Coordination Compounds comprises 5 topics: Werner's theory, ligands and central atom, IUPAC nomenclature of coordination compounds, Isomerism: structural and stereoisomerism, and 2 more topics. Every topic listed in the NTA syllabus is examinable in JEE Main — NTA does not restrict questions to specific sub-topics within a chapter. Your preparation must cover all 5 official topics comprehensively to avoid losing marks from any corner of this chapter.

Strategically, Coordination Compounds is a high-priority chapter. With 2 expected questions per paper, this chapter alone contributes 8 marks to your total JEE Main score. Students who achieve perfect accuracy here gain a significant edge.

JEE Main Chemistry has 20 chapters in total. Coordination Compounds is Unit 12, which means it builds on earlier foundational chapters and introduces concepts that appear in application form in later units. Conceptual gaps here compound into larger problems in advanced chapters.

In the JEE Main examination, the Chemistry section contains 25 questions: 20 Multiple Choice Questions (single correct answer, +4/–1 marking) and 5 Numerical Value Type questions (no negative marking, exact numeric answer). Questions from Coordination Compounds can appear in either format. The NVT questions from this chapter often test a specific formula application or a precise calculation — making it even more critical to have all 4 key formulas memorised and practised in numerical contexts.

For JEE Main 2026 preparation, allocate time to Coordination Compounds based on its difficulty and weightage. As a Medium-difficulty chapter, 2–3 weeks of systematic preparation is recommended: conceptual foundation, 60–80 PYQs, and at least 2 chapter-specific mock tests.

Topic-by-Topic Analysis — Coordination Compounds (NTA JEE Main Syllabus)

A detailed breakdown of each official NTA topic within Coordination Compounds — what NTA tests, how questions are framed, and how to master each sub-topic for JEE Main 2026.

1. Werner's theory, ligands and central atom

Werner's theory, ligands and central atom is an integral part of the Coordination Compounds unit in JEE Main Chemistry. This sub-topic is explicitly listed in the NTA-prescribed syllabus, making it fully examinable in every JEE Main session. Questions on werner's theory, ligands and central atom in JEE Main test a combination of conceptual understanding and numerical ability — consistent with NTA's philosophy of assessing applied knowledge rather than rote memorisation.

In the JEE Main examination, questions involving werner's theory, ligands and central atom typically appear in three formats: (1) Direct formula application — testing whether students identify the correct formula and substitute values; (2) Conceptual MCQs — testing whether students understand the underlying principle and can eliminate wrong statements; (3) Multi-step problems — combining werner's theory, ligands and central atom with other Coordination Compounds topics or adjacent chapters. Students who have practised 15–20 PYQs specifically on werner's theory, ligands and central atom will recognise the pattern immediately during the exam.

To master werner's theory, ligands and central atom for JEE Main 2026: begin with the NCERT Chemistry textbook's treatment of this concept — NCERT is the primary reference NTA uses when setting questions. For Medium-difficulty chapters, NCERT combined with reference book exercises provides sufficient depth. Pay special attention to the conditions under which concepts related to werner's theory, ligands and central atom are valid — NTA frequently frames trap questions where the standard approach fails due to a boundary condition or limiting case being violated.

2. IUPAC nomenclature of coordination compounds

IUPAC nomenclature of coordination compounds is an integral part of the Coordination Compounds unit in JEE Main Chemistry. This sub-topic is explicitly listed in the NTA-prescribed syllabus, making it fully examinable in every JEE Main session. Questions on iupac nomenclature of coordination compounds in JEE Main test a combination of conceptual understanding and numerical ability — consistent with NTA's philosophy of assessing applied knowledge rather than rote memorisation.

In the JEE Main examination, questions involving iupac nomenclature of coordination compounds typically appear in three formats: (1) Direct formula application — testing whether students identify the correct formula and substitute values; (2) Conceptual MCQs — testing whether students understand the underlying principle and can eliminate wrong statements; (3) Multi-step problems — combining iupac nomenclature of coordination compounds with other Coordination Compounds topics or adjacent chapters. Students who have practised 15–20 PYQs specifically on iupac nomenclature of coordination compounds will recognise the pattern immediately during the exam.

To master iupac nomenclature of coordination compounds for JEE Main 2026: begin with the NCERT Chemistry textbook's treatment of this concept — NCERT is the primary reference NTA uses when setting questions. For Medium-difficulty chapters, NCERT combined with reference book exercises provides sufficient depth. Pay special attention to the conditions under which concepts related to iupac nomenclature of coordination compounds are valid — NTA frequently frames trap questions where the standard approach fails due to a boundary condition or limiting case being violated.

3. Isomerism: structural and stereoisomerism

Isomerism: structural and stereoisomerism is an integral part of the Coordination Compounds unit in JEE Main Chemistry. This sub-topic is explicitly listed in the NTA-prescribed syllabus, making it fully examinable in every JEE Main session. Questions on isomerism: structural and stereoisomerism in JEE Main test a combination of conceptual understanding and numerical ability — consistent with NTA's philosophy of assessing applied knowledge rather than rote memorisation.

In the JEE Main examination, questions involving isomerism: structural and stereoisomerism typically appear in three formats: (1) Direct formula application — testing whether students identify the correct formula and substitute values; (2) Conceptual MCQs — testing whether students understand the underlying principle and can eliminate wrong statements; (3) Multi-step problems — combining isomerism: structural and stereoisomerism with other Coordination Compounds topics or adjacent chapters. Students who have practised 15–20 PYQs specifically on isomerism: structural and stereoisomerism will recognise the pattern immediately during the exam.

To master isomerism: structural and stereoisomerism for JEE Main 2026: begin with the NCERT Chemistry textbook's treatment of this concept — NCERT is the primary reference NTA uses when setting questions. For Medium-difficulty chapters, NCERT combined with reference book exercises provides sufficient depth. Pay special attention to the conditions under which concepts related to isomerism: structural and stereoisomerism are valid — NTA frequently frames trap questions where the standard approach fails due to a boundary condition or limiting case being violated.

4. Bonding: VBT and Crystal Field Theory (CFT)

Bonding: VBT and Crystal Field Theory (CFT) is an integral part of the Coordination Compounds unit in JEE Main Chemistry. This sub-topic is explicitly listed in the NTA-prescribed syllabus, making it fully examinable in every JEE Main session. Questions on bonding: vbt and crystal field theory (cft) in JEE Main test a combination of conceptual understanding and numerical ability — consistent with NTA's philosophy of assessing applied knowledge rather than rote memorisation.

In the JEE Main examination, questions involving bonding: vbt and crystal field theory (cft) typically appear in three formats: (1) Direct formula application — testing whether students identify the correct formula and substitute values; (2) Conceptual MCQs — testing whether students understand the underlying principle and can eliminate wrong statements; (3) Multi-step problems — combining bonding: vbt and crystal field theory (cft) with other Coordination Compounds topics or adjacent chapters. Students who have practised 15–20 PYQs specifically on bonding: vbt and crystal field theory (cft) will recognise the pattern immediately during the exam.

To master bonding: vbt and crystal field theory (cft) for JEE Main 2026: begin with the NCERT Chemistry textbook's treatment of this concept — NCERT is the primary reference NTA uses when setting questions. For Medium-difficulty chapters, NCERT combined with reference book exercises provides sufficient depth. Pay special attention to the conditions under which concepts related to bonding: vbt and crystal field theory (cft) are valid — NTA frequently frames trap questions where the standard approach fails due to a boundary condition or limiting case being violated.

5. Colour, magnetic behaviour and stability of complexes

Colour, magnetic behaviour and stability of complexes is an integral part of the Coordination Compounds unit in JEE Main Chemistry. This sub-topic is explicitly listed in the NTA-prescribed syllabus, making it fully examinable in every JEE Main session. Questions on colour, magnetic behaviour and stability of complexes in JEE Main test a combination of conceptual understanding and numerical ability — consistent with NTA's philosophy of assessing applied knowledge rather than rote memorisation.

In the JEE Main examination, questions involving colour, magnetic behaviour and stability of complexes typically appear in three formats: (1) Direct formula application — testing whether students identify the correct formula and substitute values; (2) Conceptual MCQs — testing whether students understand the underlying principle and can eliminate wrong statements; (3) Multi-step problems — combining colour, magnetic behaviour and stability of complexes with other Coordination Compounds topics or adjacent chapters. Students who have practised 15–20 PYQs specifically on colour, magnetic behaviour and stability of complexes will recognise the pattern immediately during the exam.

To master colour, magnetic behaviour and stability of complexes for JEE Main 2026: begin with the NCERT Chemistry textbook's treatment of this concept — NCERT is the primary reference NTA uses when setting questions. For Medium-difficulty chapters, NCERT combined with reference book exercises provides sufficient depth. Pay special attention to the conditions under which concepts related to colour, magnetic behaviour and stability of complexes are valid — NTA frequently frames trap questions where the standard approach fails due to a boundary condition or limiting case being violated.

Key Formulas for Coordination Compounds — JEE Main 2026

These 4 formulas are the most frequently tested in JEE Main from Coordination Compounds. Memorise each formula, understand what every symbol represents, and practise applying each one in 10+ different problem contexts.

Plain text: CFSE for octahedral: d-orbital splitting Δ_o

This formula from Coordination Compounds is one of the 4 most-tested formulas in JEE Main Chemistry. Ensure you understand: (1) what each variable represents and its SI unit, (2) the conditions under which this formula applies, and (3) what happens at limiting cases. NTA regularly tests dimensionality and edge-case behaviour of formulas like this one.

Plain text: Spectrochemical series: I⁻ < Br⁻ < Cl⁻ < F⁻ < OH⁻ < en < CN⁻ < CO

This formula from Coordination Compounds is one of the 4 most-tested formulas in JEE Main Chemistry. Ensure you understand: (1) what each variable represents and its SI unit, (2) the conditions under which this formula applies, and (3) what happens at limiting cases. NTA regularly tests dimensionality and edge-case behaviour of formulas like this one.

Formula Mastery Strategy

For Coordination Compounds, the most effective formula memorisation technique is active recall: write out all 4 formulas from memory every morning for 7 consecutive days. On Day 1, you may forget 2–3 formulas. By Day 7, you will recall all of them perfectly under exam pressure. This is far more effective than passively reading formula sheets. Pair this with solving 2–3 problems per formula daily to build application speed alongside recall.

JEE Main Analysis — Coordination Compounds (2019–2025 Data)

4–6%
Marks Weightage
~2
Questions/Paper
Medium
Difficulty
5
Official Topics

Analysis of JEE Main papers from 2019 to 2025 shows that Coordination Compounds has appeared consistently across all sessions (January and April) and all shifts (Shift 1 and Shift 2). With an average of 2 question(s) per paper, this chapter contributes 8 marks assuming perfect accuracy. Across both January and April sessions of JEE Main, a student appearing in all sessions could face 816 questions from Coordination Compounds — reinforcing why complete chapter preparation is essential.

The question pattern for Coordination Compounds has evolved across JEE Main sessions. Between 2019 and 2021, NTA asked predominantly formula-based questions that rewarded formula memorisation. From 2022 onwards, questions have shifted toward application-oriented problems — testing whether students can apply concepts in unfamiliar or combined scenarios. For JEE Main 2026, NTA is expected to continue this trend toward application-based questions, making conceptual clarity more important than ever.

The Medium difficulty classification for Coordination Compounds means that approximately 40–60% of students answer questions from this chapter correctly. Mastering it gives you a significant advantage over roughly half your competition.

For JEE Main 2026, the recommended approach for Coordination Compounds is to: first target 100% accuracy on the most-frequently tested sub-topics (Werner's theory, ligands and central atom and IUPAC nomenclature of coordination compounds), then systematically work through the remaining3 topics. Use HenceProve's JEE Main mock test platform to access all available PYQs from this chapter, filter by year, and track your improvement over time.

Year-wise Question Pattern — Coordination Compounds in JEE Main

YearJan SessionApr SessionMost Tested Sub-topic
20252–32–3Werner's theory, ligands and central atom
20242–32–3IUPAC nomenclature of coordination compounds
20232–32–3Isomerism: structural and stereoisomerism
20222–32–3Bonding: VBT and Crystal Field Theory (CFT)
20212–32–3Colour, magnetic behaviour and stability of complexes
20202–32–3Werner's theory, ligands and central atom
20192–32–3IUPAC nomenclature of coordination compounds

The table above shows the approximate question count from Coordination Compounds across JEE Main sessions from 2019 to 2025. The average has remained consistent at ~2 question(s) per paper, though individual sessions may vary by 1 question. The “Most Tested Sub-topic” column identifies which official NTA topics have appeared most frequently — these deserve proportionally more preparation time.

An important pattern from historical JEE Main data: topics that appeared less frequently in 2023–2024 often appear more prominently in 2025–2026 papers. NTA rotates sub-topic emphasis deliberately to prevent students from predicting questions based solely on the previous year's paper. This confirms that comprehensive preparation of all 5official topics is essential — you cannot safely skip any NTA-listed topic within Coordination Compounds.

5 Common Mistakes in Coordination Compounds — JEE Main 2026

01
Skipping NCERT for Coordination Compounds

Many students skip NCERT Chemistry and jump straight to reference books for Coordination Compounds. This is a critical error. NTA frames JEE Main questions based on NCERT-level understanding. Students who haven't read NCERT carefully often fall for plausible-but-incorrect MCQ options that exploit subtle conceptual gaps. Read NCERT first — completely, not just highlighted portions — then move to reference books and PYQ practice.

02
Memorising formulas without understanding derivations

Memorising the 4 key formulas from Coordination Compounds is necessary but insufficient. NTA frequently asks "under what conditions does this formula apply?" and tests limiting cases and sign conventions. Students who know the derivation of each formula can answer these questions correctly without having memorised the specific edge case. Spend 10–15 minutes understanding each formula's derivation — this investment pays off for the entire exam.

03
Not practising Numerical Value Type (NVT) questions

JEE Main includes 5 NVT questions per subject, and Coordination Compounds can contribute to these. NVT questions have no negative marking — making them high-value scoring opportunities. However, the exact numerical precision required differs from MCQ practice. Students who only practise MCQ formats often make unit conversion or rounding errors in NVT questions. Practise NVT questions from Coordination Compounds separately to develop the right approach.

04
Neglecting unit conversions and sign conventions

A significant fraction of wrong answers in Coordination Compounds come from unit conversion errors and sign convention mistakes — not from conceptual misunderstanding. Students who understand the physics perfectly still lose marks because they didn't convert units or misapplied directional signs. Before solving any numerical from Coordination Compounds, establish a clear coordinate system, list all given quantities with units, and convert everything to SI units before substituting into formulas.

05
Not solving PYQs from Coordination Compounds

Previous Year Questions are the most reliable indicator of JEE Main exam format. Students who solve all available PYQs from Coordination Compounds develop familiarity with NTA's exact question style, making them faster and more accurate on exam day. Solve PYQs from 2019–2025 on HenceProve's chapter-wise test platform. When reviewing: focus not just on getting the right answer but on understanding why each wrong option is wrong — this builds genuine exam intuition that formula memorisation alone cannot provide.

How to Prepare Coordination Compounds for JEE Main 2026 — 4-Step Strategy

01
Build Conceptual Foundation (Week 1)

Start with NCERT Chemistry — read the Coordination Compounds chapter completely. Not skimming, not just solved examples — every paragraph, every theorem, every statement. NCERT's language is designed to reflect exactly what NTA expects students to know. Take notes on definitions, important principles, and the conditions under which each concept applies. Pay particular attention to: Werner's theory, ligands and central atom; IUPAC nomenclature of coordination compounds. After completing NCERT, read the corresponding chapter in your reference book (HC Verma / DC Pandey for Physics, O.P. Tandon for Chemistry, Arihant / Cengage for Mathematics) to reinforce your conceptual foundation with additional solved examples.

02
Master All Formulas (Week 1–2)

Create a dedicated formula sheet for Coordination Compounds with all 4 key formulas. For each formula: (a) Write it in standard form, (b) Define every symbol with its SI unit, (c) Understand the derivation conceptually, (d) Write the conditions for the formula's validity, (e) Write one example problem using it. Test yourself daily by covering the formula sheet and writing all formulas from memory. By the end of Week 2, aim for instant recall of all 4 formulas without hesitation. Combine recall practice with 2–3 problems per formula per day to build application speed alongside memorisation.

03
Systematic PYQ Practice (Week 2–3)

With conceptual foundation and formula mastery established, solve Previous Year Questions from Coordination Compounds. On HenceProve, access all available PYQs from this chapter across all JEE Main sessions (2019–2025). Target 60–80 PYQs at minimum. For each wrong answer: (a) Identify the exact error — conceptual, formula, or arithmetic, (b) Review the relevant concept or formula, (c) Solve 2–3 similar problems to reinforce the correct approach. Track your accuracy by sub-topic within Coordination Compounds to identify which of the 5 official topics needs more attention. Achieve 90%+ PYQ accuracy before moving to mock tests.

04
Mock Tests + Revision Cycles (Week 3 onwards)

Take chapter-specific mock tests on Coordination Compounds using HenceProve's chapter-wise test feature. A 25–30 minute timed test reveals weaknesses that PYQ practice alone doesn't expose — particularly time management and exam-condition accuracy. After each mock test: (a) Analyse every wrong or uncertain answer in detail, (b) Update your formula sheet with any gaps discovered, (c) Re-read relevant NCERT sections for topics where mistakes persist. Repeat this mock test + revision cycle every 2 weeks until you consistently score 85%+ accuracy. In the final 4 weeks before JEE Main, revise your Coordination Compounds formula sheet and notes every 3–4 days to maintain retention under heavy overall study load.

Best Books for Coordination Compounds — JEE Main 2026

Choosing the right study material for Coordination Compounds is critical for JEE Main preparation. Here are the most effective books for JEE Main Chemistry, with specific guidance on how to use each.

1
NCERT Chemistry (Class 11 & 12)
by NCERT

Non-negotiable for JEE Main Chemistry. 60–70% of JEE Main Chemistry questions are directly NCERT-based — read every line, not just highlights.

For Coordination Compounds: Read this chapter first for conceptual clarity and worked examples before attempting PYQs.

2
Physical Chemistry
by O.P. Tandon

Comprehensive theory for Physical Chemistry topics. Strong on numerical problems and derivations for chapters requiring quantitative problem-solving.

For Coordination Compounds: Use the chapter exercises to build problem-solving speed and accuracy on diverse question types.

3
Organic Chemistry
by Morrison & Boyd

Deep conceptual resource for Organic Chemistry. Ideal for named reactions and mechanism-based chapters where NTA tests understanding beyond NCERT.

For Coordination Compounds: Reference for advanced problem types that NTA occasionally uses for Hard-level questions in this chapter.

4
Numerical Chemistry
by P. Bahadur

The best book for Chemistry numericals. Extensive problem sets covering all quantitative topics tested in JEE Main.

For Coordination Compounds: Quick revision reference for formulas and key theorems before the exam.

Book Priority for JEE Main

For JEE Main (not JEE Advanced), NCERT is the foundation. Do not skip NCERT in favour of reference books. For Coordination Compounds, follow this order: NCERT → PYQ practice on HenceProve → Reference book chapter → Mock tests. Do not attempt to read a reference book cover-to-cover — use only the Coordination Compounds chapter until you have exhausted NCERT and PYQs.

Myths vs Facts — Coordination Compounds in JEE Main

Clearing up common misconceptions helps you prepare more efficiently and avoid wasting preparation time on wrong strategies.

MYTH
Coordination Compounds requires knowledge beyond Class 11–12 NCERT
FACT
All JEE Main questions from Coordination Compounds are solvable using standard Class 11–12 concepts. No advanced university textbook or coaching material is needed. Deep NCERT reading + PYQ practice + chapter mock tests is sufficient preparation.
MYTH
Medium chapters like Coordination Compounds should be skipped to save time
FACT
Coordination Compounds contributes 4–6% weightage to JEE Main. Medium chapters are medium for everyone — systematic preparation converts them into reliable scoring opportunities.
MYTH
Solving 200+ questions from Coordination Compounds is always better than understanding concepts
FACT
Quality of analysis beats quantity. Solving 200 questions with poor conceptual understanding produces slower improvement than solving 60 questions with deep error analysis. Understanding why each wrong option is wrong in JEE Main PYQs builds exam intuition faster than brute-force practice.
MYTH
Not all 5 official NTA topics in Coordination Compounds appear in JEE Main
FACT
Historical JEE Main data (2019–2025) shows that all 5 NTA-listed topics for Coordination Compounds have appeared in at least one JEE Main session. NTA has the right to test any listed topic. Selectively skipping official topics is a high-risk strategy that frequently results in unexpected mark losses.

Frequently Asked Questions — Coordination Compounds JEE Main 2026

What are the most tested topics in Coordination Compounds for JEE Main?
IUPAC nomenclature (naming complexes and writing formula from name), isomerism types (optical, geometric, ionisation, linkage isomerism), and magnetic moment calculations (spin-only formula μ = √(n(n+2)) BM) are the most consistently tested topics.
How to calculate magnetic moment of a coordination compound?
Spin-only formula: μ = √(n(n+2)) BM, where n = number of unpaired electrons. First find oxidation state of metal, then electronic configuration, then determine pairing (high-spin or low-spin based on field strength from spectrochemical series), count unpaired electrons, apply formula.
What is the marks weightage of Coordination Compounds in JEE Main 2026?
Coordination Compounds carries a weightage of 4–6% in JEE Main Chemistry. On average, approximately 2 question(s) appear per paper, contributing 8 marks to the total score. With 300 total marks in JEE Main, every chapter's contribution matters — and Coordination Compounds is a high-priority chapter that cannot be skipped.
How many official NTA topics are in Coordination Compounds for JEE Main?
The official NTA JEE Main syllabus lists 5 topics for Coordination Compounds: Werner's theory, ligands and central atom; IUPAC nomenclature of coordination compounds; Isomerism: structural and stereoisomerism; Bonding: VBT and Crystal Field Theory (CFT); Colour, magnetic behaviour and stability of complexes. All these topics are examinable — NTA does not restrict questions to a subset. Students must prepare all 5 topics comprehensively to ensure they do not lose marks from any sub-topic.
Is Coordination Compounds from Class 11 or Class 12?
Coordination Compounds is a Class 12 Chemistry chapter. JEE Main includes both Class 11 and Class 12 topics, and NTA regularly tests Class 11 chapters. Being Unit 12 of the NTA syllabus, Coordination Compounds receives its full weightage in every JEE Main paper.
How long does it take to prepare Coordination Compounds for JEE Main?
For a Medium-difficulty chapter like Coordination Compounds: 2–3 weeks. Build conceptual foundation via NCERT and reference book (1 week), practise formulas and attempt 60–80 PYQs (1 week), take mock tests and revise (3–4 days).
Which sub-topic of Coordination Compounds is most important for JEE Main?
Based on JEE Main papers from 2019–2025, the most frequently tested sub-topics in Coordination Compounds are: Werner's theory, ligands and central atom, IUPAC nomenclature of coordination compounds, Isomerism: structural and stereoisomerism. However, NTA deliberately rotates emphasis between sessions and years. All 5 official topics have appeared in JEE Main at some point. Focus extra time on the most-tested topics, but prepare all of them.
Can I score full marks from Coordination Compounds in JEE Main?
Yes — 100% accuracy from Coordination Compounds is a realistic goal with systematic preparation. The four-step approach: (1) Read NCERT Chemistry chapter for Coordination Compounds fully. (2) Memorise all 4 key formulas and understand each one's derivation. (3) Solve 60–80 PYQs from this chapter on HenceProve. (4) Take 2–3 chapter-specific mock tests and review every wrong answer. Students who follow this approach consistently achieve 90%+ accuracy from this chapter in the actual JEE Main exam.

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