I recently wrote a utility to scan PGN files to specifically look for very bad blunders. I scanned the PGN file I used to help create my opening book and found a surprising number of games that contained queen sacrifices. I thought this may be of interest to other authors who may also use these popular PGN files that are freely available to download. I did casually check a few other chess engines and found that some do indeed contain queen sacrifices or moves that fail to capture a free queen. I guess it is very rare that these positions are actually played and therefore these bad moves are rarely discovered. I also scanned a couple of other popular PGN files available to the public and found similar number of bad games in each PGN file.
In my case, none of the positions actually made it into my opening book because of rules I have in place regarding positions that have only been played once being filtered out. But I do allow positions that have only been played once into the opening when it is played by a very strong player and they actually won the game. So it is possible that I could accidentally add a bad move to my opening book.
The following is a list of positions and moves I have found from scanning the file elo2600.pgn that you may want to check for in your opening book...
Game# 571, Move 11, - r1b1k2r/p1p1qpp1/2pp1n1p/2P5/5B2/2P1P3/P4PPP/R2QKB1R b KQkq - sm Qe5; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 12, - r1b1k2r/p1p2pp1/2pp1n1p/2P1q3/5B2/2P1P3/P4PPP/R2QKB1R w KQkq - sm Qd4; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 12, - r1b1k2r/p1p2pp1/2pp1n1p/2P1q3/3Q1B2/2P1P3/P4PPP/R3KB1R b KQkq - sm Ne4; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 13, - r1b1k2r/p1p2pp1/2pp3p/2P1q3/3QnB2/2P1P3/P4PPP/R3KB1R w KQkq - sm cxd6; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 13, - r1b1k2r/p1p2pp1/2pP3p/4q3/3QnB2/2P1P3/P4PPP/R3KB1R b KQkq - sm cxd6; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 14, - r1b1k2r/p4pp1/2pp3p/4q3/3QnB2/2P1P3/P4PPP/R3KB1R w KQkq - sm Rc1; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 14, - r1b1k2r/p4pp1/2pp3p/4q3/3QnB2/2P1P3/P4PPP/2R1KB1R b Kkq - sm Be6; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 15, - r3k2r/p4pp1/2ppb2p/4q3/3QnB2/2P1P3/P4PPP/2R1KB1R w Kkq - sm Bd3; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 16, - r3k2r/p4pp1/2ppb2p/2n1q3/3Q1B2/2P1P3/P4PPP/1BR1K2R b Kkq - sm Kd7; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 571, Move 17, - r6r/p2k1pp1/2ppb2p/2n1q3/3Q1B2/2P1P3/P4PPP/1BR1K2R w K - sm Rd1; c0 "Smirin, Ilia vs Tiviakov, Sergei 1993.??.??";
Game# 626, Move 18, - 1r1q2k1/p1p2pbp/b4np1/3N4/5B2/1P2r1PP/P2Q1PB1/1R3RK1 w - - sm Qb4; c0 "Onischuk, Alexander vs Akopian, Vladimir E 1998.10.12";
Game# 1837, Move 14, - r1b2rk1/pp2bppp/4p3/8/1n1q4/2N5/PP1B1PPP/1BRQ1RK1 w - - sm Qc2; c0 "Polgar, Judit vs Adams, Michael 1992.??.??";
Game# 1837, Move 14, - r1b2rk1/pp2bppp/4p3/8/1n1q4/2N5/PPQB1PPP/1BR2RK1 b - - sm Nc6; c0 "Polgar, Judit vs Adams, Michael 1992.??.??";
Game# 1837, Move 15, - r1b2rk1/pp2bppp/2n1p3/8/3q4/2N5/PPQB1PPP/1BR2RK1 w - - sm Nb5; c0 "Polgar, Judit vs Adams, Michael 1992.??.??";
Game# 1837, Move 15, - r1b2rk1/pp2bppp/2n1p3/1N6/3q4/8/PPQB1PPP/1BR2RK1 b - - sm Qe5; c0 "Polgar, Judit vs Adams, Michael 1992.??.??";
Game# 1837, Move 16, - r1b2rk1/pp2bppp/2n1p3/1N2q3/8/8/PPQB1PPP/1BR2RK1 w - - sm Qd3; c0 "Polgar, Judit vs Adams, Michael 1992.??.??";
Game# 4585, Move 12, - r2q1rk1/ppp1b1pp/8/n2p1p2/3Pn1b1/1QPB1N2/PP1N1PPP/R1B1R1K1 w - - sm Qa3; c0 "Yudasin, Leonid G vs Khalifman, Alexander V 1988.11.??";
Game# 4585, Move 12, - r2q1rk1/ppp1b1pp/8/n2p1p2/3Pn1b1/Q1PB1N2/PP1N1PPP/R1B1R1K1 b - - sm Nc6; c0 "Yudasin, Leonid G vs Khalifman, Alexander V 1988.11.??";
Game# 4585, Move 14, - r2q1rk1/ppp1b1pp/8/n2p1p2/3Pn1b1/1QPB1N2/PP1N1PPP/R1B1R1K1 w - - sm Qa3; c0 "Yudasin, Leonid G vs Khalifman, Alexander V 1988.11.??";
Game# 4585, Move 14, - r2q1rk1/ppp1b1pp/8/n2p1p2/3Pn1b1/Q1PB1N2/PP1N1PPP/R1B1R1K1 b - - sm Nc6; c0 "Yudasin, Leonid G vs Khalifman, Alexander V 1988.11.??";
Game# 4585, Move 15, - r2q1rk1/ppp1b1pp/2n5/3p1p2/3Pn1b1/Q1PB1N2/PP1N1PPP/R1B1R1K1 w - - sm Bb5; c0 "Yudasin, Leonid G vs Khalifman, Alexander V 1988.11.??";
Game# 4585, Move 16, - r2q1rk1/ppp1b1pp/2n5/1B1p1p2/3P2b1/Q1P5/PP1N1PPP/R1B1R1K1 b - - sm Qd6; c0 "Yudasin, Leonid G vs Khalifman, Alexander V 1988.11.??";
Game# 6717, Move 14, - r1br2k1/pp3pp1/2n1p2p/4N3/1bBP1q2/2N3P1/PP2QP1P/2R2RK1 b - - sm Qg4; c0 "Gelfand, Boris vs Benjamin, Joel L 1994.??.??";
Game# 6717, Move 15, - r1br2k1/pp3pp1/2n1p2p/4N3/1bBP2q1/2N3P1/PP2QP1P/2R2RK1 w - - sm Qe3; c0 "Gelfand, Boris vs Benjamin, Joel L 1994.??.??";
Game# 6717, Move 15, - r1br2k1/pp3pp1/2n1p2p/4N3/1bBP2q1/2N1Q1P1/PP3P1P/2R2RK1 b - - sm Ba5; c0 "Gelfand, Boris vs Benjamin, Joel L 1994.??.??";
Game# 6717, Move 16, - r1br2k1/pp3pp1/2n1p2p/b3N3/2BP2q1/2N1Q1P1/PP3P1P/2R2RK1 w - - sm Be2; c0 "Gelfand, Boris vs Benjamin, Joel L 1994.??.??";
Game# 6717, Move 16, - r1br2k1/pp3pp1/2n1p2p/b3N3/3P2q1/2N1Q1P1/PP2BP1P/2R2RK1 b - - sm Bb6; c0 "Gelfand, Boris vs Benjamin, Joel L 1994.??.??";
Game# 6717, Move 17, - r1br2k1/pp3pp1/1bn1p2p/4N3/3P2q1/2N1Q1P1/PP2BP1P/2R2RK1 w - - sm Rfd1; c0 "Gelfand, Boris vs Benjamin, Joel L 1994.??.??";
Game# 13573, Move 17, - 4rrk1/pbpn1ppp/1p1p2q1/3Pp3/2P2P2/PP2P3/1BQ1B1PP/R4RK1 w - - sm Rf3; c0 "Vyzmanavin, Alexey B vs Rozentalis, Eduardas 1983.??.??";
Game# 13573, Move 17, - 4rrk1/pbpn1ppp/1p1p2q1/3Pp3/2P2P2/PP2PR2/1BQ1B1PP/R5K1 b - - sm f5; c0 "Vyzmanavin, Alexey B vs Rozentalis, Eduardas 1983.??.??";
Game# 13708, Move 17, - 1rb1r1k1/bp3ppp/p1nq4/3N4/3p4/Q5P1/PP1NPPBP/2R1R1K1 b - - sm Re5; c0 "Miles, Anthony J vs Chandler, Murray G 1984.??.??";
Game# 13708, Move 18, - 1rb3k1/bp3ppp/p1nq4/3Nr3/3p4/Q5P1/PP1NPPBP/2R1R1K1 w - - sm Nf4; c0 "Miles, Anthony J vs Chandler, Murray G 1984.??.??";
Game# 13708, Move 18, - 1rb3k1/bp3ppp/p1nq4/4r3/3p1N2/Q5P1/PP1NPPBP/2R1R1K1 b - - sm Ra5; c0 "Miles, Anthony J vs Chandler, Murray G 1984.??.??";
Game# 13708, Move 19, - 1rb3k1/bp3ppp/p1nq4/r7/3p1N2/Q5P1/PP1NPPBP/2R1R1K1 w - - sm Qb3; c0 "Miles, Anthony J vs Chandler, Murray G 1984.??.??";
Game# 15076, Move 14, - 1rb1qr1k/pp2p2p/n4bp1/2pp4/2PPp3/2N2NP1/PPQ2PBP/3R1RK1 w - - sm Qxe4; c0 "Tukmakov, Vladimir B vs Malaniuk, Vladimir P 1986.??.??";
Game# 15076, Move 14, - 1rb1qr1k/pp2p2p/n4bp1/2pp4/2PPQ3/2N2NP1/PP3PBP/3R1RK1 b - - sm Bd7; c0 "Tukmakov, Vladimir B vs Malaniuk, Vladimir P 1986.??.??";
Game# 15730, Move 13, - r1bq1rk1/pp3pbp/n5p1/3p4/1n6/P1N3P1/1P2NPBP/R1BQ1RK1 w - - sm Qxd5; c0 "Bareev, Evgeny I vs Lputian, Smbat G 1987.??.??";
Game# 15730, Move 13, - r1bq1rk1/pp3pbp/n5p1/3Q4/1n6/P1N3P1/1P2NPBP/R1B2RK1 b - - sm Nc6; c0 "Bareev, Evgeny I vs Lputian, Smbat G 1987.??.??";
Game# 19008, Move 20, - r2r3k/pq2bppp/2p1bN2/1p1nB1P1/7Q/P2B1P2/1PP4P/2KR3R b - - sm a5; c0 "Chandler, Murray G vs Wahls, Matthias 1990.11.??";
Game# 21918, Move 16, - r3r1k1/1p1nqpb1/p2p1np1/P1pP2Bp/2P5/2N2B1P/1PQ2PP1/R4RK1 b - - sm Nh7; c0 "Kaidanov, Gregory S vs Kamsky, Gata 1993.12.??";
Game# 21918, Move 17, - r3r1k1/1p1nqpbn/p2p2p1/P1pP2Bp/2P5/2N2B1P/1PQ2PP1/R4RK1 w - - sm Bd2; c0 "Kaidanov, Gregory S vs Kamsky, Gata 1993.12.??";
Game# 22070, Move 9, - r2qk2r/pp1n1ppp/2p1pn2/5b2/PbBP4/2N1PN2/1P3PPP/R1BQ1RK1 w kq - sm Qc2; c0 "Beliavsky, Alexander G vs Akopian, Vladimir E 1993.??.??";
Game# 22070, Move 9, - r2qk2r/pp1n1ppp/2p1pn2/5b2/PbBP4/2N1PN2/1PQ2PPP/R1B2RK1 b kq - sm Bg6; c0 "Beliavsky, Alexander G vs Akopian, Vladimir E 1993.??.??";
Game# 23298, Move 20, - r3k2r/pp1b1pp1/4n3/4Ppqp/N2Q4/3B2P1/PPP2P1P/R3K2R w kq - sm Qe4; c0 "Leko, Peter vs Hertneck, Gerald 1994.12.??";
Game# 23298, Move 20, - r3k2r/pp1b1pp1/4n3/4Ppqp/N3Q3/3B2P1/PPP2P1P/R3K2R b kq - sm O-O-O; c0 "Leko, Peter vs Hertneck, Gerald 1994.12.??";
Cheers,
Tom.
Does your opening book have any queen sacrifices?
Moderator: Ras