Solubility Science: Principles and Practice

A free eBook linked to the apps in Practical Solubility Solubility Science: Principles and Practice Abbott

Updated March 2021 with Crystallization - plus two YouTube videos Crystallization Part 1 of 2 and Crystallization Part 2 of 2

Everything I've learned whilst developing Practical Solubility and formulating in the real world is brought together in my book Solubility Science: Principles and Practice. 241pp & 100k words. It contains lots of good science, with links that take you straight from the book into your default browser to explore the relevant app within Practical Solubility. It is completely free and is not tied to any advertising or email list and doesn't require registration.

It turns out that just 5 key approaches can answer most of your solubility needs. The book concentrates on these ideas which are:

  1. Ideal Solubility: The highest solubility you can expect from a solute
  2. Hansen Solubility Science: the workhorse technique used in a wide range of solubility formulation issues
  3. COSMO-RS: the most powerful solubility theory there is
  4. DLVO, Zeta and a few other dispersion science ideas
  5. Kirkwood-Buff theory, the least known and the most insightful theory, especially for more complex solubility issues.

Those who prefer alternative solubility theories should read the book to see why I chose not to focus on them.


  1. Solubility Basics
    • A few rather simple core concepts that take us a long way.
  2. Transforming Solubility Thinking
    • Why you really do want to understand Kirkwood-Buff solubility theory!
  3. Hansen Solubility Parameters
    • The general-purpose solubility science for practical formulators.
    • The most powerful and fundamental way to calculate solubility phenomena.
  5. Dispersions
    • Useful tools for understanding how to keep dispersions stable.
  6. Solubilizers
    • An important area of solubility science properly explained.
  7. Aqueous Solubility
    • Facing up to the realities of what goes on in water.
  8. Green Solubility
    • If you are going to save the planet with green solubility, then do it properly, not via greenwash.
  9. Diffusion and Solubility
    • Diffusion and solubility are closely related, so it is important to understand how and why.
  10. The New Language of Solubility
    • A lot of our solubility problems come from asking the wrong questions, framed by the language we use. The right language leads to the right questions, and the answers can be found much more easily.
  11. Crystallization
    • By thinking of solubility issues behind crystallization we can more quickly find the right solvent system. Then by using the new lanague of "clusters" we can better understand nucleation and crystal growth.

Creative Commons BY-NDThe book is Copyright © 2017-21 Prof Steven Abbott and is distributed under the Creative Commons BY-ND, Attribution and No-Derivatives license.


You just click to download it and start reading in the format of your choice. By linking to Practical Solubility you get all the benefits of the live apps. On an iPad, for example, a click on a link takes you to see it in Safari and a 4-finger swipe allows you to go back and forth between book and app. On a laptop it's even easier to swap between the two views.

You can download it in any format(s) you find useful. The table of contents in each of the formats (including PDF) is "live" so it is very easy to find what you want. Most eBook readers have a search function so the book doesn't need or have an index. You can choose your reading experience. Some like to read page-by-page but it can be difficult if a diagram or a formula is on a different page in your specific view. Others like a scrolling view which is less book-like but is easier to move back and forth to check diagrams and formulae.

With formats other than PDF there is an issue about footnotes. The best eReaders allow pop-up footnotes which just appear when you click them, but such support is erratic so I have placed all footnotes at the end of the paragraph - the least bad option.

  1. PDF. Solubility Science Principles and Practice.pdf. [If you want to download it, use right click.] On a high-res tablet or laptop, PDFs offer a good reading experience and it is the simplest to get going; on a smartphone it may be less pleasant to read.
  2. ePub3. Solubility Science Principles and Practice.epub. This works on phones, tablets, PCs, Macs with modern ePub3 readers such as iBooks, Calibre, Azardi, IceCream etc. How do you get it into, say, iBooks? I use Dropbox on my iPad and choose iBooks to run it. You may find other ways via, say, email.


Version Information

  • 18 March 2021.
    • A few extras for crystallization following helpful feedback.
  • 1.0.2 15 March 2021.
    • A new chapter on crystallization.
  • 5 April 2020.
    • A number of typos fixed thanks to the careful checking of Lee McManus
  • 5 January 2018.
    • An important update on calculating RDF and KBI for large irregular solutes such as proteins, using the recent "minimum distance" approach of Martínez and Shimizu
  • 5 October 2017.
    • Some HSP updates on temperature effects and on water and on IGC
    • Change of footnotes to end of paragraph mode for eReaders
  • 1.0.0 15 September 2017.
    • Initial release

One of the joys of producing my own book and giving it away is that I can rapidly respond to the reader community. I can quickly fix typos, reword passages that are unclear, improve the layout within a given reader. More importantly, if there is science that is incomplete, wrong or missing I am happy to do my best to fix the problem. I can't do this without your help, so please email me at if you want me to make improvements.

Where does the science come from?

My task has been to find the good, useful scientific principles and distill them into words and apps that allow people like me to use the principles in practice. In addition to reading books and many 100's of academic papers, I've had the chance to meet and learn from some of the great modern solubility scientists and many that I haven't met have most generously helped me via email. All through the book, and in any app where I needed help with the algorithm, I acknowledge their generous inputs. All the credit for the science goes to them. All the blame for errors in describing and implementing their science goes to me.

Happy reading!

My Royal Society of Chemistry book chapters

This book is written in a deliberately informal style. For those who want to pursue some of my arguments in more academic detail, I have co-authored two book chapters for the Royal Society of Chemistry with Dr Seishi Shimizu at U York.