Mention a specific potential adviser and project in the PhD statement of purpose I am writing my statement of purpose for my Ph.D. and I want to work in a specific field with a specific professor in the department that I am going to apply for and I have a very good experience in this field. I sent an email for that professor asking if he/she is accepting Ph.D. students and he/she did not respond. I built my whole statement of purpose based on my previous achievements and future plan for that specific area. I also mentioned that I am willing to work with that professor. My statement of purpose tells that I am very passionate about this field and I am only willing to work with that professor (if there were more than one professor working on the same area, I would mention all of them). if that professor doesn't accept new Ph.D. students, will I risk my admission to that school? 

Will the committee response be something like this:  "the applicant really knows what he/she is going to do and there is a specific future plan and he/she also got a good experience in this field, but he/she sounds very strict to his plan and doesn't show any flexibility...REJECTED"?
Stating specific professors you want to work with can be a good idea usually I feel. It shows that you have researched the school individually and are not just sending out blanket applications. It also allows for the admissions committee to see a developed idea of what you plan on studying. Whenever I review applications for graduate school, I always like to see that an applicant has given some thought to what they actually want to specifically study. Even if their listed topic is not what they end up studying, I can at least see that they are capable of determining a specific research direction.

All of this being said, it can be a bit risky as an applicant to base your entire application on a single professor and topic. You ask the following question:


  If that professor doesn't accept new Ph.D. students, will I risk my admission to that school?


The answer to that question is unequivocally "yes." An admissions committee is not likely to accept a student who is extremely rigid in their proposed plan of study if said plan of study will not be feasible. (E.g. saying "I will only work with Dr. McDonald because she is the expert in the field of rubber chickens. This is only topic I am interested in." when Dr. McDonald is not available to take on more students). Departments on the whole do not like students (or professors) who are inflexible in their research (and teaching) goals. 

My advice would be to present your first choice professor as just that, your leading choice. I would then also present one or two other options as backup plans of sort. 


  I am quite interested in doing research on polymer composition of imitation foliage with Dr. Thomas York. His latest paper on the subject is exactly the type of project for which I want to develop a greater ability. Fake plastic trees is a field that I foresee myself enjoying immensely and I believe Dr. York to be one of the principal leaders on the topic. I am also intrigued by the work of Dr. Linda Petrovic and Dr. Ron Bobb on kettle drums. I have taken several classes using kettle drums and would enjoy pursuing research on the sociological implications of taking kettle drums to funerals. Dr Petrovic's work on the topic introduced me to several questions I had never considered before.  


You will ultimately need to decide whether it would be better to be admitted to the school of your choice and potentially not study your chosen topic, or to be rejected from the school of your choice and maybe study your chosen topic elsewhere.